Geology on EARTH Magazine

Folding drone flies into tight spaces

Tue, 19 Mar 2019 15:51:50 -0400

A new drone can fold itself to squeeze through gaps and then return to its previous shape, all while continuing to fly. Credit: UZH.

Drones can go many places humans can’t, and a new foldable drone is squeezing into even tighter, more dangerous places than ever before. Inspired by birds that can fold their wings in midair to fly through cramped spaces, researchers have created a drone that can fold into various configurations while maintaining stable flight.

Geoethics in the Field: Leading by Example

Tue, 19 Mar 2019 15:27:56 -0400

This shirt is intended to be funny, but we geoscientists should respect both physical and ethical boundaries when working in the field. Credit: Scott E. Foss.

In May 2015, five people associated with a college field trip, including students, stole 60 pounds of dinosaur bones from Bureau of Land Management-administered land in Utah. The bones were recovered, the offenders were charged with varying degrees of theft and they eventually pleaded guilty. Luckily, such egregious incidents are uncommon, but smaller instances of vandalism by professional geoscientists are more common — for example, cutting something out of an outcrop on national park land.

Grounding Asian jumping worms

Wed, 13 Feb 2019 16:31:47 -0500

Asian jumping worms, which can decrease the availability of nutrients in soils for microbes, plants and fungi, have been on the rise in Wisconsin and other states. Credit: Geological Society of America.

To tell the difference between a regular earthworm and an Asian jumping worm, pick it up. An earthworm will likely just lay there, perhaps curling gently around a finger, but a jumping worm will thrash around violently until it jumps out of your grasp. Researchers are looking at how this invasive species is altering soil in Wisconsin, where the worms have been found in growing numbers since 2013.

Abiotic amino acid found in subseafloor rocks

Wed, 13 Feb 2019 16:21:38 -0500

A carbonate chimney observed in 2005 at the Lost City hydrothermal vent field. Researchers recently determined that an amino acid detected in rock deep below the field was likely formed through abiotic processes, shedding light on how early biomolecules might have first formed. Credit: NOAA.

In 2000, scientists discovered a new type of deep-sea hydrothermal vent site in the North Atlantic about 20 kilometers west of the Mid-Atlantic Ridge, which they named Lost City. Nearly two decades later, researchers have discovered that an amino acid detected in rocks beneath the site is produced by a geochemical process, rather than a biological one. The find reveals conditions that might have kick-started life on Earth.

Kerogen's nanostructure determines oil and gas reservoir capacity

Wed, 13 Feb 2019 16:12:45 -0500

At left is a digitized image of the exterior of a kerogen sample; at right is a three-dimensional image of its internal pore structure as revealed by electron tomography. Credit: Roland Pellenq/MIT.

The petroleum and natural gas that power engines and heat homes are extracted from the complex networks of nooks and crannies that permeate kerogen — a waxy organic mishmash that forms within sedimentary rocks as algae, terrestrial plants and other organic matter is compacted and heated over geologic time. In a new study, scientists have taken the closest look yet at kerogen’s internal pore structure, and the resulting images are helping scientists understand why some oil and gas reservoirs are more productive than others.

Stronger monsoon drove ancient Indus civilization into the hills

Wed, 13 Feb 2019 15:57:41 -0500

Roughly 4,000 years ago, the Indus River Valley was home to the advanced and thriving Harappa culture. But by 1800 B.C., the civilization’s sophisticated cities along the river, which drains into the Arabian Sea on the coast of what is now Pakistan, were abandoned for smaller villages in the Himalayan foothills. A new study suggests that widespread changes in the Indian winter monsoon may have resulted in flooding that forced people to resettle farther from the Indus.

Benchmarks: March 31, 1933: The Civilian Conservation Corps is established

Wed, 13 Feb 2019 15:23:50 -0500

Civilian Conservation Corps (CCC) workers plant trees in Wisconsin in 1937. Across the U.S., the CCC planted more than a billion trees, reclaiming large swaths of forest land that had been logged during the preceding century. Credit: Library of Congress.

On Jan. 25, 1938, a heavy winter snowstorm struck Wisconsin, blocking the road connecting Blackwell to the nearest hospital 10 kilometers away in Laona. The storm left Blackwell resident Stella Simonis, an expectant mother who was hours away from delivering her child, snowed in with no way to get to the hospital, according to an Associated Press article that ran in several Wisconsin papers the next day.

Geomedia: Books: "How the Rock Connects Us" shares copper country geoheritage

Wed, 13 Feb 2019 15:04:12 -0500

"How the Rock Connects Us: A Geoheritage Guide to Michigan's Keweenaw Peninsula and Isle Royale," by Bill Rose, Erika Vye and Valerie Martin, Isle Royale and Keweenaw Parks Association, 2017, ISBN 9780935289213

There is extensive literature on Michigan’s “Copper Country,” but most existing publications on the subject are either technical reports or anecdotal recountings of exploration, mining and life in the “wilderness.” A recent book, “How the Rock Connects Us: A Geoheritage Guide to Michigan’s Keweenaw Peninsula and Isle Royale” — written by Bill Rose and Erika Vye, both of Michigan Tech University, with Valerie Martin, a longtime Isle Royale interpretive ranger — fills a long-standing need for a readable, user-friendly explanation of how familiar Keweenaw landscapes and recent mining history are related to the area’s underlying geology. It is an eye-opener.

Geomedia: Books: A witty look at "The Ends of the World"

Wed, 13 Feb 2019 14:59:21 -0500

"The Ends of the World: Volcanic Apocalypses, Lethal Oceans, and Our Quest to Understand Earth's Past Mass Extinctions," by Peter Brannen, Ecco/Harper-Collins, 2017, ISBN 9780062364807; paperback published 2018, ISBN 9780062364814

Our planet has been through some harrowing episodes, particularly in the form of mass extinctions since the advent of multicellular life. How organisms came to perish in these events should interest all conscious, intelligent forms of multicellular life lucky enough to still be alive — you and I included. A great way to satisfy that interest is with “The Ends of the World: Volcanic Apocalypses, Lethal Oceans, and Our Quest to Understand Earth’s Past Mass Extinctions” by Peter Brannen, a well-paced, well-sourced and well-written guide to mass extinctions.

Geologic Column: Newspeak for kids

Wed, 13 Feb 2019 14:52:35 -0500

Credit: Bruce Mars from Pexels

“Once upon a time, words began to vanish from the language of children. They disappeared so quietly that at first almost no one noticed — fading away like water on stone. The words were those that children used to name the natural world around them: acorn, adder, bluebell, bramble, conker — gone!” – Robert Macfarlane, "The Lost Words"

Travels in Geology: Finding Florida's hidden freshwater gems

Wed, 13 Feb 2019 14:29:26 -0500

The largest of the 30 springs at Florida's Silver Springs State Park is called Mammoth, or Main, Spring. No swimming is allowed here, but visitors can view the spring from a glass-bottom boat tour. Credit: Bethany Augliere.

As a child, my family and I often traveled to Florida to escape the chilly Virginia winters and enjoy the Sunshine State’s warm sunny beaches. Occasionally, we’d make a trip to Orlando to visit one of the theme parks or stop at Everglades National Park to search for alligators, snakes and birds.

Getting there and getting around Florida

Wed, 13 Feb 2019 14:18:07 -0500

Camping and canoeing are popular pastimes on Florida's Peace River. Credit: both: Bethany Augliere.

For travelers flying in from out of state, Florida has several major airports, including in Miami (MIA), Orlando (MCO) and Tampa (TPA), as well as numerous other options. Orlando is the most central large hub and may be the best option if you’re heading toward the state’s springs, which are concentrated in the north-central part of the state. For traveling to and between sites, a car is the best option.

How to become a cave diver

Wed, 13 Feb 2019 14:15:22 -0500

While snorkeling the spring pools is cool (no pun intended), a more in-depth way to experience Florida’s freshwater springs is to scuba dive in them. However, entering the caves requires you to get a cave diving certification. That’s because cave diving has inherent challenges distinct from scuba diving’s own challenges. Even after you’re familiar with buoyancy control, breathing control and how to work your gear (all part of getting scuba certified), there’s much to learn about the specifics of cave diving. For example, if you kick incorrectly and stir up silt in an underwater cave, you can lose visibility and quickly become disoriented, which can turn deadly. Because of this, some of the most important parts of training involves learning about cave environments and talking about the psychological aspects of cave diving, along with emergency procedures, of course.

Piecing together the big picture of coral reef health

Wed, 13 Feb 2019 13:40:43 -0500

Reefscape from Koror State, Palau. Credit: Brian Zgliczynski, 100 Island Challenge (100IC), Scripps Institution of Oceanography (Scripps).

Today, news of damaged or devastated coral reefs has become commonplace. Reefs face many threats, including bleaching, disease, overfishing, pollution and even invasive species. While the fates of the reefs may seem almost universally bleak, some scientists think the future of these vital marine ecosystems could be more complicated — and perhaps even hopeful.

Art joins science in coral communication

Wed, 13 Feb 2019 13:25:14 -0500

Diane Burko's work on display at the National Academy of Sciences in Washington, D.C. (above left), includes the painting Faga'alu (above right; 60x60 inches, acrylic on canvas, 2018), which was inspired by her visit to coral reefs in American Samoa, Credit: above left: Kevin Allen; above right: Diane Burko.

Scientists are not alone in their quest to observe and understand how coral reefs change through time. Artists and researchers have been creating stunning paintings, movies and even soundscapes to examine how reefs are responding to environmental pressures. Art has the power to engage viewers in scientific inquiry when they least expect it, reaching new audiences and facilitating public awareness.

Hot but not bothered: Warm soils favor microbes with small genomes

Thu, 07 Feb 2019 16:17:08 -0500

A stretch of abandoned road in Centralia, Pa., where a subterranean coal seam fire has been burning for decades, altering conditions in overlying soils. Credit: courtesy of MSU

Centralia, Pa., sits above rich subterranean coal seams, which made the town a mining center for about a century. In 1962, the seams were accidentally ignited by burning garbage, turning the coal from a commodity into a liability. Nearly 57 years later, the ground beneath Centralia is still smoldering.

Thirsty mantle: Subduction zones swallow more water than thought

Wed, 30 Jan 2019 15:26:27 -0500

A seismic study of part of the Pacific Plate diving beneath the Mariana Trench has revealed that old and cold subducting plates, like the Pacific, likely carry a lot more water into the mantle than previously realized. Credit: K. Cantner, AGI

For all the water stored in oceans, ice and other reservoirs at Earth’s surface, there’s likely even more in the planet’s interior, where it plays important roles in many geological processes, including the formation of magma and the lubrication of earthquake-producing fault zones. Uncovering just how much water is inside Earth — and the extent to which it moves back and forth between the surface and subsurface — has long been a challenge for scientists interested in understanding the planet’s water cycle. A new study peering beneath the Mariana Trench in the Western Pacific has revealed that some subduction zones might pull significantly more water into Earth’s interior than previously thought.

Mineral Resource of the Month: Boron

Tue, 29 Jan 2019 14:39:49 -0500

By Amanda Brioche, USGS mineral commodity specialist

PRODUCTION

GEOLOGIC OCCURRENCE

Sodium borates, also known as borax, have a monoclinic prismatic crystal structure. Credit: Aram Dulyan, photograph taken at the Natural History Museum, London.

Boron does not occur in nature in an elemental state. It is always found in oxidized states as borate salts. Four mineral forms account for the majority of the economically viable borate deposits throughout the world: two sodium borates, tincal and kernite; a calcium borate, colemanite; and a sodium-calcium borate, ulexite. Borate deposits are formed in areas that are tectonically active with arid climates. Large deposits are found in the Mojave Desert of the United States near Boron, Calif., the Tethyan belt in western Asia and the Andean belt of South America. Most borates are extracted in California and Turkey.

Beryllium: the rain bringeth and the rain taketh away

Thu, 17 Jan 2019 13:39:49 -0500

A study of soils in the Kohala region of Hawaii's Big Island revealed that high rainfall and weathering rates affect the accuracy of beryllium-10 as a tracer of soil age and processes. Credit: Eric Tessmer, CC BY 2.0.

High in Earth’s atmosphere, cosmic rays collide with oxygen atoms, shattering the oxygen into smaller atoms, including radioactive beryllium-10. Atmospheric beryllium-10 that falls to Earth’s surface — in precipitation or aboard dust particles — is known as meteoric beryllium-10. Researchers often use the ratio of meteoric beryllium-10 to nonradioactive beryllium-9 in soil as a tracer of soil age and processes. As beryllium-10 has a long half-life — about 1.4 million years — scientists have used it for studies of both short- or long-term soil dynamics.

Seismometers eavesdrop on glacial outburst flood

Thu, 17 Jan 2019 13:36:13 -0500

The Bhotekoshi Valley in Nepal before and after the 2016 flood of the Sunkoshi River. Credit: both: Kristen Cook/GFZ.

On July 5, 2016, a previously dammed glacial moraine in Nepal burst, releasing 100,000 tons of water that barreled down the Sunkoshi River, destroying bridges, hydropower plants and roads in its path. The flood was so massive that ground shaking was felt throughout the river corridor and recorded by seismometers deployed in the wake of the April 2015 Ghorka earthquake.

Easter Island inhabitants drank brackish water to survive

Thu, 17 Jan 2019 13:33:07 -0500

Graduate student Tanya Brosnan, who led a recent study of coastal seeps — where fresh groundwater flows into the ocean — on Rapa Nui (Easter Island), carries out conductivity measurements near Ahu Tongariki on the east side of the island. Credit: Carl Lipo.

The remote Chilean island of Rapa Nui, also known as Easter Island, is famous for its 961 giant stone statues and monuments, erected between 1200 and 1600. Called moai, these statues have been a mystery for years, especially considering just a few thousand people inhabited the small, resource-limited Pacific island nearly 3,700 kilometers west of Chile. “Why did people put the statues where they did?” asks Carl Lipo, an archaeologist at Binghamton University in New York. The answer, according to new research, may have something to do with the civilization’s water supply.

Lab-grown magnesite a boon for carbon sequestration?

Thu, 17 Jan 2019 13:29:51 -0500

Left undisturbed, carbonate minerals can naturally lock up carbon in a stable form for millions of years or longer. Triggering the formation of carbonate minerals is thus a promising means of removing and sequestering carbon dioxide from the atmosphere. In recent research, scientists uncovered new details about how one of Earth’s most stable, albeit slow-to-form, carbonates — magnesite — grows in nature and have found a way to accelerate its formation in the lab at room temperature. The results could aid in developing efficient carbon sequestration technologies.

Humans accidentally created new rivers in Europe

Thu, 17 Jan 2019 13:26:26 -0500

The Lek River in the Netherlands formed as a result of avulsion triggered by human alteration of the surrounding landscape. Credit: Rijkswaterstaat/Joop van Houdt.

Meandering rivers that flow through and transport sediment to deltas often split off from their main courses and flow in different directions. This process, called avulsion, happens naturally when a river overflows its banks and the floodwaters carve out a new course for the river to follow. But humans can also trigger avulsions by changing the shape of the landscape, and in a new study, scientists report that people have been doing this for a very long time.

Archaeologists hit pay dirt in medieval latrines

Wed, 16 Jan 2019 16:27:26 -0500

Archaeologists digging in Lübeck, Germany, unearthed an unusual source of information about past dietary habits in the city: parasite eggs recovered from 700-year-old latrines.

Researchers excavated fecal samples dating from the 12th through the 17th centuries from latrines in eight medieval houses in the city, which was a busy Baltic Sea trading port in the Middle Ages. Using microscopic techniques and analyses of preserved DNA, they identified parasitic worms in the samples. While they found high counts of roundworm eggs in samples spanning the roughly 500-year period studied, there was a notable shift in the presence of eggs from different types of tapeworms, the team reported in Proceedings of the Royal Society B.

Mighty Mekong cut by monsoon, not tectonics

Wed, 16 Jan 2019 16:24:18 -0500

The Mekong River is the longest river system in Southeast Asia, flowing through six countries. Here, the river flows through Yunnan province in China, where it's known as the Lancang River. Credit: shutterstock.com/HelloRF Zcool.

The rivers draining the Tibetan Plateau are some of the largest, longest and most deeply incised waterways in the world. For decades, most geologists assumed that these river canyons were cut as the plateau was uplifted following the initial collision of the Indian subcontinent with Asia. However, recent studies have found that the plateau was already elevated by 40 million years ago — roughly 20 million years before the deep canyons formed. In a new study, researchers have identified a different force driving the Mekong’s incision: intensification of the Asian monsoon starting about 17 million years ago.

Mediterranean heritage sites threatened by rising seas

Tue, 15 Jan 2019 14:25:49 -0500

With threats from storm surge and coastal erosion, the Venetian lagoon is one of the most endangered UNESCO World Heritage sites in the Mediterranean. Credit: ©Lena Reimann, Sally Brown.

The Mediterranean region has been a cultural center for centuries, giving rise to numerous locales designated as UNESCO World Heritage sites. A new study looking at the effects of rising sea levels on treasures like the Venetian Lagoon, the Old City of Dubrovnik and the ruins of Carthage indicates that most UNESCO sites on the Mediterranean Sea are at risk of storm surge and coastal erosion as well as inundation in the coming decades.

Mineral Resource of the Month: Garnet

Tue, 15 Jan 2019 13:50:15 -0500

Wollastonite with embedded andradite garnet ore from New York. Credit: Kenneth C. Curry.

PRODUCTION

Geologic Occurrence

Garnet is the general name given to a group of complex silicate minerals, all with isometric crystal structure and similar properties and chemical composition. The most common garnet minerals are classified into three groups: the aluminum-garnet group, the chromium-garnet group and the iron-garnet group. Worldwide, garnet resources are large and occur in a wide variety of rocks, principally in metamorphic rocks such as gneisses and schists. Garnet also occurs in veins, contact metamorphic rocks, metamorphosed crystalline limestones, pegmatites and serpentinites. In addition, alluvial garnet sands are associated with heavy-mineral sand and gravel deposits in many parts of the world.

Geologic Column: Is this land really your land?

Tue, 15 Jan 2019 13:33:54 -0500

Credit: Adobe stock photo/Petar

In 1940, after traveling across America from Oklahoma to New York City, Woody Guthrie wrote the iconic folk song “This Land Is Your Land.” He had quickly tired of hearing Kate Smith’s 1938 rendition of Irving Berlin’s “God Bless America” blaring from jukeboxes along the route and regarded that song’s portrayal of America as a land of equality for all as misleading. Guthrie thought that corporations and the wealthy disproportionately owned or controlled too much private property, according to a 2012 NPR report. Guthrie felt that lower- and middle-class folks needed a reminder that America belonged just as much to them as to the ultrarich and powerful, and he drafted “This Land” as a protest song. In fact, the song was originally titled “God Blessed America for Me,” a sarcastic rejoinder to Berlin’s tune. Countless renditions of “This Land” have cultivated the song into what many contend is a second national anthem.

Travels in Geology: Mid-ocean volcanic excursion: The calderas and caldeiras of the Azores

Fri, 11 Jan 2019 16:32:53 -0500

One of the most beautiful places in the Azores, the caldera of Sete Cidades is ringed by hiking trails and trachytic pumice. Credit: Kat Cantner and Colin McFadden.

In the middle of the Atlantic, 1,600 kilometers off the coast of Portugal, lie the Azores, an archipelago comprising nine remote islands, each with its own history, culture and geology worth exploring. Visitors to São Miguel, the largest island, can bathe in a hot spot in the ocean thanks to an unusual geothermal outflow. On Faial, they can view remnants of the most recent eruption that devastated the island. Meanwhile, Santa Maria offers opportunities to see the only fossils in these volcanic islands.

Getting there and getting around Azores

Fri, 11 Jan 2019 16:29:05 -0500

Hiking is a popular way to get around on Faial and throughout the Azores. Credit: Kat Cantner and Colin McFadden.

The Azores are unique, highly accessible and packed with activities. There are direct flights to Ponta Delgada (PDL) from Boston and New York, as well as from Lisbon and Porto in Portugal if you’re coming from Europe. Moving between the islands is fast and affordable via flights on SATA Air Azores, the local airline. You can also opt for a ferry, though the journey will take quite a bit longer. Be aware that weather changes quickly in the Azores, so it’s not uncommon for flights to be delayed, or to end up landing at alternative airports. Just go with the flow.

Sounding Out Earth's Hum

Fri, 11 Jan 2019 16:01:16 -0500

Scientists are working to isolate and identify the various sources and mechanisms of Earth's vibrations. Credit: Lucia Gualtieri, based on seismic data from the Incorporated Research Institutions for Seismology (IRIS); background: Adobe stock photo/Andrej Pol.

Earth has a song, a symphony composed of ubiquitous, continuous subtle seismic signals that thrum beneath the hustle and bustle of modern society. Scientists first observed this ambient seismic noise — everything recorded on seismograms that cannot be attributed to earthquakes — at the end of the 19th century. Since then, they have been trying to determine what causes it, how to measure and track it, and how to use the information from it.

Redefining Dinosaurs: Paleontologists are Shaking the Dinosaur Family Tree to its Roots

Fri, 11 Jan 2019 15:45:10 -0500

The current dinosaur family tree, which is fundamentally based on differences in hip morphology, has been in use since 1887. Scientists have recently proposed reorganizing some of the tree's biggest branches. Credit: K. Cantner, AGI.

What traits distinguish one dinosaur from another? For many, that question probably conjures characteristics like the massive jaws of tyrannosaurs, the distinctive horns and plates of ceratopsids and stegosaurs, and the exceedingly large bodies of sauropods and their kin. But for paleontologists looking to classify different dinosaurs, it’s all about the shapes, or morphologies, of the animals’ bones.

Melting glaciers shift Earth's axis

Fri, 21 Dec 2018 11:15:54 -0500

A perfectly round desk globe spins evenly on a fixed axis, but that’s not the case with Earth, which wobbles as the position of its spin axis — the imaginary line running between the North and South poles — slowly drifts over time. In a new study in Earth and Planetary Science Letters, scientists suggest that there are three main reasons for the movement of Earth’s spin axis, called polar motion.

Ocean circulation change suffocating Gulf of St. Lawrence

Fri, 21 Dec 2018 11:03:00 -0500

Research suggests that the Gulf Stream is shifting to the north, such that it's impinging on the flow of the Labrador Current near the Tail of the Grand Banks and reducing the supply of well-oxygenated water to the Gulf of St. Lawrence. Credit: K. Cantner, AGI.

Estuaries are among the most nutrient-rich and biologically productive areas of the ocean, and the Gulf of St. Lawrence, where freshwater from the Great Lakes and the St. Lawrence River meets the salty Atlantic Ocean in eastern Canada, is the largest estuary in the world. But the biodiversity and long-thriving fisheries of the Gulf of St. Lawrence could be threatened by declines in oxygen levels over the last half century. A new study suggests that a large-scale shift in Atlantic Ocean circulation is dumping warmer, oxygen-poor water into the gulf.

Rising carbon dioxide may raise risk of nutrient deficiencies in humans

Fri, 21 Dec 2018 10:54:40 -0500

In a new study, researchers found that levels of zinc, iron and protein in some grains and legumes will drop as atmospheric carbon dioxide concentrations rise. Credit: public domain.

Plants absorb carbon dioxide to fuel their growth. As humans increase the amount of the greenhouse gas in the atmosphere, more will be available to vegetation around the world. But according to a new study, too much carbon dioxide might eventually lead to plants that are deficient in key nutrients for humans, which could be especially detrimental in the developing world.

Columbia River basalts erupted faster than thought

Fri, 21 Dec 2018 10:49:09 -0500

Lava flows of the Wanapum Basalt, the second-youngest formation of the Columbia River Basalt Group (CRBG), are exposed in Palouse Falls State Park along the Palouse River in eastern Washington. Researchers recently found that most of the CRBG lava erupted over a period of about 758,000 years, faster than previously thought. Credit: Jennifer Kasbohm, Princeton University.

Editor’s note: This story appeared in print in the January issue of the magazine. The version below has been updated to note that the areal extent of the Columbia River Basalt Group (CRBG) exceeds 200,000 square kilometers. This value was previously given as 163,700 square kilometers. Additionally, the story has been amended to acknowledge prior research that suggested that more than 90 percent of the CRBG volume erupted over a roughly 1.1-million-year period.

Arctic warming causes Siberian cooling

Fri, 21 Dec 2018 10:45:48 -0500

New research suggests that Siberia's anomalously cold winters in recent years may have been caused by melting sea ice in the Barents-Kara Sea. Credit: Dmitry A. Mottl.

The Arctic is warming faster than anywhere else on Earth, and fall sea-ice extents have been trending downward for decades. But while the region is heating up, that northerly warming seems to be having the opposite effect on some midlatitude locations: Parts of Siberia near the Ural Mountains, for example, have had anomalously cold winters in recent decades.

Ancient collision left a bit of Europe behind in Britain

Fri, 21 Dec 2018 10:37:02 -0500

The ancient landmasses of Laurentia, Avalonia and Armorica collided 400 million years ago, contributing pieces to the island that is today Great Britain. Credit: K. Cantner, AGI.

Great Britain is famously considered the birthplace of modern geology, and the many layers and terranes of rocks that make up England, Wales and Scotland have been studied and mapped for centuries. But that doesn’t mean scientists fully understand the island’s geologic past. In a new study, researchers looking at unusual volcanic rocks in southern England found previously unrecognized evidence of the island nation’s past connection to mainland Europe.

The geology of kidney stones revealed

Fri, 21 Dec 2018 10:31:39 -0500

Kidney stones are an excruciatingly painful problem for 10 percent of the world’s population. In a new study applying geobiological methods to the study of human kidney stones, researchers have shed light on how the stones form, and revealed that they partially and repeatedly dissolve inside the kidney — which could help in developing new protocols to treat the pervasive affliction.

Oman ophiolite suggests subduction started with a shove

Fri, 21 Dec 2018 10:28:47 -0500

Past research has suggested two mechanisms by which subduction zones may form along an area of lithospheric weakness: spontaneous sinking of denser crust and lithosphere, and forced convergence driven by lateral movement of a plate. A new study suggests that the latter was responsible for the formation of a fossil subduction zone off the Arabian Peninsula beginning about 104 million years ago. Credit: K. Cantner, AGI.

Plate tectonics is a fundamental control on how Earth operates and is important for the planet’s habitability, but how this crustal recycling process got started has long been a mystery. A new study examining some uniquely coupled metamorphic and volcanic rocks in Oman is adding some needed clarity about the initiation of subduction zones, a critical component in plate tectonics.

Down to Earth With: Clay mineralogist Warren Huff

Fri, 21 Dec 2018 10:11:59 -0500

Clay mineralogist Warren Huff taught at the University of Cincinnati (UC) for 55 years. He is still active as a professor emeritus and is a great supporter of bringing UC alumni together, especially at Geological Society of America annual meetings. Credit: courtesy of Warren Huff.

Two distinct images come to mind when I think of Warren Huff, my former doctoral adviser: one in which he is enthusiastically teaching and mentoring students both in and out of the classroom, and one in which he is sitting around a fire, playing guitar and leading a group of geologists in science-themed sing-alongs. Both images encapsulate the kind of person he is: a leading scholar in the field of clay mineralogy who lives life with gusto.

Geologic Column: Muinntir a' ghlinne so

Fri, 21 Dec 2018 10:06:22 -0500

"Pibroch" signifies a Scottish piper's variations on a musical theme. Credit: Alberto Garcia, CC BY-SA 2.0.

“The Gaelic word “pibroch” isn’t one you come across every day. It signifies a Scottish piper’s variations on a musical theme. Although the theme may often be warlike, many pibrochs are laments for the “tears of things,” the lacrimae rerum, or tragedy of existence, of which the old Romans wrote. In 1966, Dionne Warwick turned the popular song “Alfie” — which was composed for the movie of the same name and opened with the iconic line “What’s it all about, Alfie?” — into a poignant lament for human existence that always reminds me of a pibroch.

Comment: How to tell a good science story

Thu, 20 Dec 2018 11:44:54 -0500

The relative shapes of selected paradigms for science stories. Solid black lines show the relationship between the main character's fortune and the progression of a story from start to finish, relative to an average day (dotted line). Credit: figure shared with permission from Canadian Science Publishing under CC BY 4.0.

Everyone has a story to tell. Scientists are no exception, especially given that scientific studies can take researchers to far-flung places around the planet, lead to amazing new discoveries about the world we live in and produce challenges that provide the drama that is so important for a great story. Stories have the power to transport listeners to the places and experiences the storyteller is sharing with them. What better way is there to show that science is relevant, exciting and conducted by people who are passionate about what they do?

Our top tips for adding storytelling to your repertoire

Thu, 20 Dec 2018 11:40:22 -0500

(from Green et al., Facets, February 2018)

Identify your take-home message first. Start with the end in mind.

Remember the shape of your story. Tracking the main character’s fortune over time moves the story forward.

Consider the scale and timing of your story. Cut irrelevant background, processes and methods if they don’t move the story forward in a compelling way.

Eyes in the sea: Swarms of floating robots observe the oceans

Tue, 18 Dec 2018 12:31:05 -0500

When Scripps biological oceanographer Peter Franks needed a way to mimic planktonic movements in the ocean, Scripps research oceanographer Jules Jaffe created low-cost "miniature autonomous underwater explorers," or M-AUEs. The M-AUEs can be deployed in swarms to track planktonic movements as well as small-scale circulation patterns, oil spill dispersion or even sewage movement. Credit: Jaffe Lab for Underwater Imaging, Scripps Oceanography, UC San Diego.

In 1999, Peter Franks, a biological oceanographer at Scripps Institution of Oceanography in San Diego, published a hypothesis that, to his knowledge, nobody had previously considered. Using a mathematical model, he showed how tiny zooplankton and phytoplankton could interact with ocean currents driven by internal waves — slow-moving waves within the ocean that form between water layers of differing density — and form patchy bands running parallel to shorelines. These patches of plankton could benefit from being squeezed together by wave action, he thought, by being better able to feed, survive or even reproduce.

Travels in Geology: Lhasa, Tibet: Journey to the roof of the world

Tue, 18 Dec 2018 11:23:06 -0500

No visit to the windswept Tibetan Plateau would be complete without seeing Mount Everest, the world's highest peak. Credit: Lon Abbott and Terri Cook.

Few destinations are as alluring as the wild and windswept Tibetan Plateau. With an average elevation of 4,500 meters, it is Earth’s highest tableland and one of the most isolated regions on the planet. Tibet’s capital, Lhasa, one of the world’s highest cities, is simply breathtaking — both literally, given the low oxygen levels at this altitude, and figuratively, with its mountainous backdrop and the gleaming whitewashed walls of Potala Palace, an enduring symbol of Tibetan Buddhism, rising high above the Old Town. As we saw firsthand when our family visited last summer, Lhasa — with its intricately painted statues, gilded-dome stupas housing Buddhist relics, and thousands of prayer wheels glistening in the flickering light of yak-butter candles — is a place that’s both above and apart from the rest of the world.

Getting there and getting around Tibet

Tue, 18 Dec 2018 11:21:22 -0500

“Tibet is a long way from most everywhere. There are no direct flights from North America, so it’s usually cheapest and most convenient to fly into a major Chinese city such as Beijing and then catch the next flight to Lhasa Gonggar Airport (LXA). Air China, Tibet Airlines, Sichuan Airlines and China Southern are among the carriers offering direct and connecting flights to Lhasa from most major Chinese cities. Sichuan Airlines and Air China also provide nonstop service from Kathmandu, Nepal. The Lhasa airport is located 65 kilometers south of the city center and takes about an hour to reach.

Sulfides in thawing permafrost responsible for carbon dioxide release

Fri, 30 Nov 2018 16:42:03 -0500

An area of permafrost collapse, called a thaw slump, on the Peel Plateau in Canada's Northwest Territories exposes buried minerals in long-frozen soil to the elements at the surface. Credit: Scott Zolkos

After warming the bench since the Pleistocene, a key player in the Arctic carbon cycle is getting back in the game thanks to thawing permafrost. In a new study, researchers report that rising temperatures are freeing sulfide minerals previously bound within Arctic permafrost. These minerals are contributing to stream acidification and accelerated weathering of carbonates — and thus to the release of carbon dioxide into the atmosphere — at least in one part of northern Canada.

Geomedia: Gifts: Holiday Gift Guide

Fri, 09 Nov 2018 10:55:07 -0500

Gifts can be hard to find for the geek that’s got it all. If the science devotees in your life have already collected every piece of science memorabilia, or cleared out the shelves in the gift shop at their favorite museum, this guide might be just the solution. From inventive home and office items to engaging toys for kids, EARTH has curated a list of unique, fun gifts that any science lover would be happy to receive.

Travels in Geology: Touring the Capital Geology of Washington, D.C.

Fri, 09 Nov 2018 10:06:48 -0500

The rushing whitewater and jagged rocks of Great Falls, along the Potomac River about 20 kilometers upstream of downtown Washington, D.C., make for one of the most striking natural scenes in the metropolitan area. Here, the river is gradually incising the Piedmont province's hard rocks, oceanic sedimentary rocks that were metamorphosed during Appalachian mountain building roughly 460 million years ago. Credit: ©iStockphoto.com/DouglasRissing.

Washington, D.C., is one of the biggest centers of power on the planet — a nexus of domestic and international politics, backroom deal-making and patriotic reflection. But there is so much more to D.C. than politics. Among its other attributes, the D.C. metro area is a powerhouse of scientific research, and more specifically geoscience research. It’s home to institutions like the U.S. Geological Survey, the Carnegie Institution for Science, the Smithsonian Institution, the National Institute of Standards and Technology, and the headquarters of NASA and NOAA, along with a slew of universities, advisory and lobbying groups such as the National Academy of Sciences, the American Geosciences Institute (which publishes EARTH) and the American Geophysical Union, which this month will host its annual fall meeting in the city. D.C. is also home to numerous longstanding geological interest groups, including the Potomac Geophysical Society, the Paleontological Society of Washington and the 125-year-old Geological Society of Washington.

Revealing the ghosts of glaciers past

Fri, 09 Nov 2018 09:42:19 -0500

Locations of highlighted glaciers of the Rockies. Credit: K. Cantner, AGI.

Glaciers are one of the most powerful erosive agents on Earth, capable of pulverizing entire mountain ranges into dust. These rivers of ice grind over high-elevation landscapes, leaving behind striking pyramidal peaks, knife-edge arêtes, classic U-shaped valleys, deep bowl-shaped cirques and rocky moraines. Glaciers advance and retreat — and thicken and thin — as the balance shifts between snow accumulation and ice melt. But, according to the World Glacier Monitoring Service, the recent global trend has been toward more melting, meaning that glaciers on all seven continents have been receding.

"Critical Minerals" list snubs copper, sparks discussion of criticality

Thu, 08 Nov 2018 13:03:34 -0500

Many people think copper ought to be on the U.S. list of critical minerals, but it was left off in part because the U.S. has a fairly robust domestic supply from mines such as Bingham Canyon Copper Mine in Utah. Credit: Doc Searls, CC BY 2.0.

In 2017, the United States relied on imports for more than half the needed supply of 50 mineral commodities that are critical in manufacturing. Some of the commodities come from just a few major suppliers — especially China and Canada — or are produced in tiny quantities in just a few places. Others come from conflict zones. Some are produced only as byproducts of processing ores of major metals, such as copper and zinc. Such complex international supply chains are at risk of being disrupted by a variety of problems, from trade wars and market volatility to natural disasters and terrorism.

Survey says: U.S. lakes getting murkier

Thu, 08 Nov 2018 13:01:01 -0500

Lake McDonald in Glacier National Park (top) is still clear, but a new study reports that many lakes across the U.S., like Como Lake in Minnesota (above), are getting murkier. Credit: left: Mary Caperton Morton; right: K. Cantner.

A study of more than 1,000 lakes across the United States between 2007 and 2012 found that the number of murky green and brown lakes surpassed the number of clear blue lakes.

Bubbly discovery may impact volcanic hazard assessment

Thu, 08 Nov 2018 12:58:37 -0500

Researchers monitored gases as they streamed out of the lava lake in Halema'uma'u Crater on Kilauea in 2013 (above) and found that the gas activity changed rapidly, which meant the hazard also changed rapidly. By June 2018 (left), the lava lake had disappeared. Credit: both: USGS.

Programs that manage volcanic hazards use a variety of tools and techniques to monitor impending eruptions. But researchers recently found evidence — in the form of gas bubbles bursting out of Hawaii’s Kilauea Volcano — suggesting that scientists should forgo one common method for assessing hazards from basaltic volcanoes: averaging gas composition measurements.

Did early agriculture knock the climate off track?

Thu, 08 Nov 2018 12:49:15 -0500

A new study indicates that animal husbandry and agriculture starting about 8,000 years ago (depicted here in a painting from the burial chamber of the Egyptian artist Sennedjem from about 3,300 years ago) postponed the next glacial period. Credit: public domain.

During the last 2.5 million years, Earth’s climate has seen cycles of advancing and retreating glaciers over much of the Northern Hemisphere. We are currently in a warm, interglacial period — one that’s been prolonged by increases in atmospheric concentrations of greenhouse gases, such as carbon dioxide and methane. According to a new study in Nature, these high concentrations of greenhouse gases have disrupted the recent pattern of cycling in Earth’s climate and pushed back the next ice age. The study also suggests that human activity, beginning thousands of years ago with early agriculture and continuing through to the present day, has fueled the rise in greenhouse gas concentrations.

Science by floats

Thu, 08 Nov 2018 12:46:27 -0500

The Southern Ocean Carbon and Climate Observations and Modeling project (SOCCOM) set out four years ago to study the Southern Ocean and its role and influence on global climate. The main mission of the project was to increase Southern Ocean observations, especially during the frigid winter months, to better understand climate change and biogeochemistry.

Southern Ocean is absorbing less carbon

Thu, 08 Nov 2018 12:44:12 -0500

Since 2014, autonomous floats have been making continuous observations of the biogeochemical characteristics of the Southern Ocean. Scientists are using this information to make estimates of carbon fluxes to refine climate change models. Credit: left: Melissa Miller; right: Isa Rosso.

In the Southern Ocean surrounding Antarctica, complex and dynamic interactions among the atmosphere, cryosphere, and surface and deep ocean waters play an important role in climate. Although it covers only a quarter of Earth’s oceanic surface area, the Southern Ocean — with its cold temperatures and carbon-sucking algal blooms — has been estimated to take up 40 percent of anthropogenic carbon dioxide emissions. However, new data collected by a fleet of autonomous floating sensors show that the Southern Ocean is taking up significantly less carbon than scientists thought.

Fats on Neolithic pottery pinpoint climate cooling event

Thu, 08 Nov 2018 12:39:20 -0500

Çatalhöyük, in what is now central Turkey, was once a thriving Neolithic settlement, home to as many as 10,000 people. Credit: Çatalhöyük Research Project.

About 8,200 years ago, right around the time that animals such as cows and sheep were first being domesticated in the Near East for meat and milk, the planet underwent a cooling event that lasted about 160 years. How this cold snap, known as the 8.2-kiloyear event, affected early farmers has long been a mystery, as archaeological evidence from the period of the cooler and drier climate has been scant. But new research investigating fatty residues preserved on scraps of pottery found at the UNESCO World Heritage site of Çatalhöyük in Turkey is offering some clues.

Forecasting California's earthquake hazard

Thu, 08 Nov 2018 11:20:05 -0500

This figure shows the likelihood of earthquake occurrences in California over different timescales using a new physics-based model (left column) and the UCERF3 hazard model (middle column). The right column shows the ratio between the results of the two models. Credit: Shaw et al., Science Advances, August 2018, CC BY-NC 4.0.

In California, scientists use a model called the Uniform California Earthquake Rupture Forecast (UCERF3) to assess earthquake hazards across the state based not on the physics of the state’s faults, but on history: By considering the historic record of earthquakes, including the location and severity of past quakes, UCERF3, the third version of the model, provides a hazard measure. “But those observations are limited, because we only have a few hundred years [of written earthquake records] in California,” says Greg Beroza, a seismologist at Stanford University. “In the long term, we have a small sample of the possible behavior of the system.” This means the resulting hazard assessments, relying on the relatively short historical earthquake record, may not accurately reflect earthquake potential across the state. So, scientists have long been trying to come up with physics-based models that show how particular faults might rupture without depending on historical records — and now, they have.

Antarctic rift was active more recently than thought

Thu, 08 Nov 2018 10:54:19 -0500

The West Antarctic Rift system split the continent into two plates for 200 million years before becoming inactive about 11 million years ago, after which the two plates drifted back together. The rift is responsible for the volcanoes that still exist on Antarctica. Credit: K. Cantner, AGI.

Studying Antarctica’s geology is difficult because of the continent’s remote location and extreme weather, and because most of it is buried under kilometers of ice. More than 100 volcanoes hint at the White Continent’s fiery history, however. Scientists have long known that Antarctica was once split into two plates along the West Antarctic Rift system. A new study provides information about when this rift system was last active, and the findings have implications for calculating plate tectonic movements around the planet.

Geologic Column: Light amid the darkness: Celebrations during the winter solstice

Thu, 08 Nov 2018 09:35:25 -0500

Ancient Scandinavians celebrated the Feast of Juul (Yule) with a log burned on the hearth to honor Thor, whose job was to bring the sun's warmth, light and life-giving properties back to the people. In Scandinavian customs, the log never burned entirely as it was used as a starter log for the next year's fire. Other cultures also celebrated with a Yule log, but most burned it completely to use the ashes on their fields as fertilizer, wear the ashes as charms or put them under their beds for protection. Credit: ©iStockphoto.com/Ptahi.

This year, the winter solstice falls on Friday, Dec. 21, marking the arrival of winter and the shortest stretch of daylight of the year in the Northern Hemisphere (the situation is reversed in the Southern Hemisphere). The solstice occurs simultaneously around the world when the sun is directly over the Tropic of Capricorn, the line of latitude 23.5 degrees south of the equator. On Dec. 21, winter will officially arrive at 5:23 pm (EST).

Comment: Learning "Minecraft" as a forty-something proves the game can be an educational tool for all ages

Thu, 08 Nov 2018 08:59:32 -0500

The "Minecraft Education" renewable energy module and lesson plan — which was based on an interactive curriculum developed by the author and colleagues — introduces students to alternative energy concepts by having them build homes that use renewable energy. Credit: Mojang ©2018/Microsoft Studios.

“Minecraft” is an insanely popular game. By 2018, more than 140 million copies had been sold, making it the second-best-selling video game in history, after “Tetris.” First released in 2009 by the Swedish game developer Mojang, the popularity of the sandbox-type game — so-called because it allows players to build unique structures and environments within different worlds — grew rapidly. In 2014, Mojang was acquired by Microsoft for $2.5 billion.

Comment: National Geological Surveys: The past, present and future

Thu, 08 Nov 2018 08:50:28 -0500

The most basic goal of national geological surveys is to map the geology of the country. This map, the first complete geological map of Britain, was published by William Smith in 1815, 20 years before the British Geological Survey — the world's first — was formed. Credit: William Smith, scan by the Library Foundation, Buffalo and Erie County Public Library.

The world’s oldest national geological survey is 183 years old; the youngest is 19. These two, and every other one out there, represent countries with vastly different needs — while some surveys are focused on overarching goals like natural resource sustainability, others are still working to map the fundamental geology of their lands. Yet there’s much that brings them together now and will continue to in the future.

Congress, states look to address impacts of ocean acidification

Tue, 16 Oct 2018 10:46:56 -0400

Shellfish such as oysters are a big business in the Pacific Northwest, but some places have seen mass mortalities of larvae in recent years due to acidic oceans. Credit: Rick Obst, CC BY 2.0.

Global ocean chemistry is changing at a historically unprecedented rate, with rising ocean acidity threatening populations of shellfish and other marine species worldwide. Recent observed changes in ocean chemistry off U.S. coasts, particularly along the shores of Alaska, California, Oregon and Washington, where fisheries are already being affected, have scientists studying the potential impacts, fishermen worrying about their livelihoods, and politicians pushing for action.

Mercury on the roof of the world

Tue, 16 Oct 2018 10:31:23 -0400

Mercury, the only metal that is liquid at room temperature, is extremely toxic to humans and has detrimental effects if excreted into the environment. Credit: Hi-Res Images of Chemical Elements (CC by 3.0)

Traditional Tibetan Medicines (TTM) are dispensed in pill form by pharmacists who mix minerals and herbs together in centuries-old recipes. But some of the ingredients may be doing more harm than good. Previous studies have found that mercury and methylmercury, both highly toxic to humans, are sometimes intentionally used in the medications. In a new study, published in Environmental Science & Technology, researchers analyzed total mercury and methylmercury concentrations in seven common TTM remedies and found concentrations as high as 12,000 micrograms per gram and averaging 5,600 micrograms per gram. They found that daily mercury intake by Tibetans who practice traditional medicine was as much as 3,000 times higher than exposure rates in the general populations in Japan, Norway and the U.S.

"Easy bake" fossils resemble real deal

Tue, 16 Oct 2018 10:27:45 -0400

The method to simulate fossilization can also be used onfeathers. Credit: The Field Museum.

A new method to simulate fossilization can be used on much larger samples than previous methods, including whole lizard heads and feet. Credit: The Field Museum.

Most fossils are millions of years in the making, but a new technique is allowing scientists to simulate the process of fossilization in about 24 hours. The laboratory-based method, described in a study published in the journal Palaeontology, sheds light on how exceptionally preserved fossils form generally over geologic time and may provide custom samples for research projects investigating specific conditions under which certain fossils formed.

Scientists discover granite crystallizes at lower temperatures

Tue, 16 Oct 2018 10:25:01 -0400

Under an electron microprobe, areas in this quartz crystal that are bluer indicate higher concentrations of titanium and higher crystallization temperatures. Credit: Michael Ackerson.

Investigating the properties of granite has given researchers insight into how gold and other economically important ores are produced, the thermal properties of Earth’s crust, the state of magma in active volcanic regions, and how Earth’s continents formed. “The temperature of granite crystallization underpins our thinking about many of these phenomena,” researchers note in a new study in Nature. “But evidence is emerging that this temperature may not be well constrained,” added the study authors, who found that certain granites crystallize at temperatures as much as 200 degrees Celsius lower than previously thought.

Gulf Stream eddies transport iron to North Atlantic subtropical gyre

Tue, 16 Oct 2018 10:20:31 -0400

New research shows that counterclockwise-rotating cold eddies are transporting iron from the Gulf Stream into the North Atlantic subtropical gyre. Credit: NASA Goddard Space Flight Center Scientific Visualization Studio.

Dust from the Sahara Desert is a major supplier of iron to the North Atlantic subtropical gyre — the huge circular ocean current stretching between North America and the west coasts of Africa and Europe — where cyanobacteria use the scarce nutrient to fuel nitrogen fixation, which then fertilizes other organisms at the base of the marine food chain. Now, researchers have discovered that eddies spinning off the Gulf Stream also transport iron to the northwestern edge of the gyre.

Winter precipitation in southwestern U.S. tied to Kiwi Coast

Tue, 16 Oct 2018 10:18:16 -0400

New research suggests a strong negative correlation between fall sea-surface temperatures off the north coast of New Zealand and winter precipitation in the southwestern U.S. If, for example, there are lower-than-normal sea-surface temperatures north of New Zealand, there is a much higher chance for a wet winter in Southern California and the southwestern U.S. Credit: K. Cantner, AGI, after Mamalakis et al., Nature Communications, June 2018.

Water supplies in the southwestern United States largely depend on winter precipitation. Predicting seasonal rain and snowfall is becoming more difficult, however, as climate change causes precipitation patterns to vary. A new study provides evidence of a strong correlation between late-summer to fall sea-surface temperatures off the coast of New Zealand and winter precipitation in the southwestern U.S. — a correlation that could help provide earlier and more reliable forecasts for the southwestern U.S., and improve water resource and ecosystem management in the region.

Japanese diaries show sun's cycle sparks lightning on Earth

Tue, 16 Oct 2018 09:40:44 -0400

New research links lightning to the 27-day solar rotational cycle. Credit: ©iStockphoto.com/mdesigner125.

The effects of solar cycles on Earth’s climate over timeframes of thousands of years are well documented, but the shorter-term effects on weather are less understood. A new study using ancient Japanese diaries to track storms in the 18th and 19th centuries suggests that one of the sun’s shortest cycles — the 27-day rotational period — may play a role in stimulating lightning on Earth.

Getting There & Getting Getting Around Monti Sibillini National Park

Mon, 15 Oct 2018 10:46:15 -0400

Views of hillside orchards and the nearby Sibillini Mountains await visitors to the Al Respiro nel Bosco bed-and-breakfast in the foothills just outside the northern boundary of Monti Sibillini National Park. Credit: Callan Bentley.

For those traveling internationally by air to Italy to visit Monti Sibillini National Park, flying into Rome’s Leonardo da Vinci–Fiumicino Airport (FCO) is likely the best option. Florence is another option, but Rome is closer and hosts more flights. There are several routes into the park from different directions; all the entrance points on the western side of the park are a two-and-a-half- to three-hour drive east of Rome. Bus tour services run out of Rome, but the best way to reach the park is via rental car. Rental cars are plentiful, and the good news is that, unlike driving in some parts of Italy such as around Naples or in Sicily (which is not for the faint of heart), driving in the Apennines is much more like driving in the U.S. In this part of Italy, drivers are more courteous and generally adhere to road signage and lane guidelines. All countries have driving norms that are not immediately clear to foreign drivers, however. In Italy, to avoid scorn from your fellow drivers, it’s important to remember to never pass another car on the right. Italians consider it a severe breach of driving etiquette.

Travels in Geology: Jewel of the Apennines: Italy's Monti Sibillini National Park

Mon, 15 Oct 2018 10:29:31 -0400

Monte Vettore, the highest peak in the Sibillini Mountains at 2,476 meters elevation, rises above the Piano Grande, or "Great Plain," at left. The summit is reachable by several hiking paths, the most popular of which traverses 5 kilometers from the roadside Forca di Presta trailhead (foreground) to the peak, crossing fault scarps formed in the past two years during large, damaging earthquakes. Credit: Alan Pitts.

The Apennine Mountains form the exposed, rocky backbone of Italy. In northwestern Italy, the mountains are linked to the Maritime Alps; from there, they wind sinuously southward in the form of several arcuate chains all the way to the southern terminus of the Italian Peninsula, where they disappear under the Gulf of Taranto before reappearing on Sicily as part of the Calabrian Arc. In the central Apennines, roughly three hours from Rome by car, Monti Sibillini National Park straddles the border between the regions of Umbria to the west and Marche to the east. The park offers exemplary views into the formation of Italy’s limestone spine, as well as several chilling lessons about the relationship between humans and the unstable land on which we live.

Going subterranean: Repurposed mines become innovative labs

Mon, 15 Oct 2018 10:13:05 -0400

A technician works inside a roughly 500-cubic-meter neutrino detector during its construction in April — one of two liquid argon detectors being built at the European Organization for Nuclear Research's (CERN) facility near Geneva, Switzerland. Known together as ProtoDUNE, the detectors at CERN are prototypes of four larger versions to be built at the Sanford Underground Research Facility (SURF) — housed in the former Homestake Gold Mine near Lead, S.D. — as part of the Deep Underground Neutrino Experiment (DUNE). Credit: CERN.

The headframe of the historic Soudan Iron Mine on a frigid day in northern Minnesota. The mine, which ceased operations in 1962, is now operated as a state park and also hosts scientific research. Credit: Josh Knackert.

At about 5 a.m. on a frigid, icy February day in northern Minnesota — the kind of day when it feels like your eyeballs might freeze — a group of about 10 undergraduates in a geobiology course at the University of Minnesota-Duluth jumped onto a bus, headed for a destination far more temperate and out of the elements — or, rather, deep below the elements. Joined by their professors, microbiologist Cody Sheik and geologist Latisha Brengman, as well as a few others (including yours truly), the students arrived, two hours later and still before daybreak in the Minnesota Northwoods, at the visitor center and museum for the historic Soudan Iron Mine. The mine began operations in 1882 as an open pit mine, but moved underground about 20 years later and ceased mining in 1962.

Turning modern "eyes" on ancient sites

Fri, 12 Oct 2018 13:19:52 -0400

Researchers used different datasets to uncover Jerash's past, because each dataset showed something different. 1) High-resolution photography revealed a stone wall not visible in other datasets. 2) Lidar clearly revealed another wall that was poorly defined in aerial photography. 3) Clearing up distortions in this 1953 photo revealed a possible structure defined by highlight and shadow that was obscured by a modern road in 2015 and by vegetation in 1939. 4) This wall from the 1939 aerial photo was not visible in other datasets. Credit: Danish-German North-West Quarter Project.

People have inhabited Jerash, Jordan, since the Neolithic. But much of its history has been buried by subsequent occupation, including over the last two centuries. Archaeologists have excavated Jerash with trowels and screens to uncover its long history, but now, with the help of lidar and old photographs, a team of researchers is discovering more about Jerash’s past by gazing down on the city from the sky.

Algae ate themselves to death and caused a global extinction

Fri, 12 Oct 2018 13:14:37 -0400

A new study suggests that enhanced burial of carbon from eukaryotic algae drew down atmospheric carbon dioxide levels during the Ordovician, resulting in a diminished greenhouse effect that triggered an ice age and a mass extinction. Credit: Callan Bentley, 2018.

Errant asteroids and toxic emissions from volcanic eruptions are the usual suspects in mass extinctions. But during the Ordovician, it was a million-year stretch of cooling ushered in by proliferating algae that triggered a worldwide glaciation and extinction event, according to a new study.

Saharan dust a storm killer

Fri, 12 Oct 2018 13:11:29 -0400

NASA satellite imagery shows Saharan dust crossing the Atlantic Ocean into the Gulf of Mexico, where the dust may suppress developing storm systems. Credit: NASA/Texas A&M University.

Each year between 900 million and 4 billion metric tons of dust from the Sahara Desert in Africa is swept into the atmosphere and blown around the world. In places like Texas, the dust often leads to poor air quality. A new study suggests that desert dust may also suppress the formation of severe storms and hurricanes in the southern United States.

Globe-trotting kelp set new world record

Fri, 12 Oct 2018 13:03:55 -0400

Kelp grows in underwater forests in shallow regions of temperate, tropical and polar oceans. Air bladders in the leaves enable the seaweed to travel vast distances on currents across oceans. Credit: public domain.

When marine biologist Erasmo Macaya, from University of Concepción in Chile, found a piece of kelp washed up on a beach in Antarctica, he suspected the scrap of seaweed had come a long way.

Underwater WiFi? Rising sea levels threaten physical internet

Fri, 12 Oct 2018 13:02:04 -0400

On this map of Miami, blue areas are projected to be underwater by 2118, according to NOAA. Undersea, long-haul and local metro fiber cables are shown, respectively, in red, green and black. Credit: Paul Barford, UW-Madison.

It seems like you can find wireless internet almost anywhere now, but the backbone of the internet is wired: Infrastructure such as fiber optic cables, data centers, traffic exchanges and hubs keeps us connected. In many coastal cities, however, these critical communication pieces are facing increasing risk from rising seas. A new study shows that thousands of kilometers of cables and hundreds of internet traffic hubs will be inundated by rising sea levels in the next 15 years, putting coastal cities like New York, Miami and Seattle at risk for widespread disruptions.

Benchmarks: November 16, 1990: Florida Keys National Marine Sanctuary is established

Fri, 12 Oct 2018 12:51:58 -0400

Designated in November 1990, the Florida Keys National Marine Sanctuary protects nearly 10,000 square kilometers of ocean surrounding the islands, including North America's only barrier reef. Credit: K. Cantner, AGI.

Off the tip of the Florida Peninsula lies the world’s third-largest living coral reef, the Great Florida Reef. The only barrier reef system in North America, it is composed of a system of individual reefs that together extend 270 kilometers south of Miami through the Florida Keys, a crescent-shaped chain of more than 1,500 islands, about 30 of which are inhabited. This ecological treasure is home to more than 6,000 species of marine life, including colorful fish and endangered sea turtles, as well as extensive seagrass beds, mangrove islands and about 1,000 shipwrecks.

Down to Earth With: Geologist Robert Brinkmann

Fri, 12 Oct 2018 12:40:44 -0400

Geologist Robert Brinkmann is vice provost for scholarship and research and dean of graduate studies at Hofstra University in New York. Credit: Robert Brinkmann.

As a child, Robert Brinkmann was always curious about rocks. He wondered how they got where they were and why they were different from each other. Brinkmann grew up in the farm country of southeastern Wisconsin, as well as in the woods in the northern part of the state. After one of his first geology classes in college, he went home and finally understood what he was looking at. “It was such an eye-opening experience to be able to read the landscape,” Brinkmann says.

Comment: Making social media work for scientists

Fri, 12 Oct 2018 11:09:44 -0400

Scientists at the Norwegian Polar Institute (NPI) in Norway run a science outreach initiative using the handle @oceanseaicenpi. These photos were used in posts from their Instagram (www.instagram.com/oceanseaicenpi), Twitter (twitter.com/oceanseaicenpi) and Facebook (www.facebook.com/oceanseaicenpi) platforms. Credit: clockwise from top left: Elina Nystedt (NPI), Paul A. Dodd (NPI), Jon Aars (NPI), Sebastian Gerland (NPI), Anja Rösel (NPI), CopernicusEU/Mikhail Itkin (NPI), Peter Leopold (NPI), Nick Cobbing (National Geographic), Amelie Meyer (NPI).

Whether true or not, scientists are famous for not being great public communicators, yet communication is a key aspect of our work. Traditional science communication involves sharing findings with colleagues through published articles in peer-reviewed journals and presenting work at conferences. Scientists are encouraged to communicate using this well-defined framework and are rewarded for doing so; in fact, our career progress is often assessed using such publication records. Meanwhile, communication with wider audiences might entail visits with schoolchildren or perhaps talking to journalists for stories in a magazine like this one. But sharing findings with and promoting science to the public is a less-defined task, and often one with few incentives and little support. That communicating with wider audiences isn’t encouraged is unfortunate considering many of us are funded by the public to research and answer questions relevant to society. We should clearly communicate our findings to the public, especially regarding complex topics such as climate change.

Mineral Resource of the Month: Phosphate

Mon, 10 Sep 2018 13:08:22 -0400

By Stephen M. Jasinski, USGS mineral commodity specialist

PRODUCTION

GEOLOGIC OCCURRENCE

Phosphate rock refers to unprocessed ore and beneficiated concentrates that contain some form of apatite, a group of calcium phosphate minerals. Apatite in phosphate rock is the primary source for phosphorus in phosphate fertilizers. More than 80 percent of the world’s current production of phosphate rock is mined from sedimentary deposits, which were formed by the deposition of phosphate-rich materials in marine regions. Most of the rest comes from igneous deposits of carbonatites and silica-deficient intrusions. The grade of phosphate rock is classified by the phosphorus pentoxide content.

Ecuadorian volcano plays its pipe

Mon, 10 Sep 2018 11:44:11 -0400

The once-visible floor of Cotopaxi's summit crater dropped out of sight after the 2015 eruptions. Credit: both: Silvia Vallejo Vargas/Instituto Geofisico, Escuela Politécnica Nacional.

An active volcano in central Ecuador may be the largest musical instrument on Earth: After eruptions in 2015, Cotopaxi’s newly configured crater started emitting distinctly musical rumblings that scientists may be able to use to monitor future activity at the volcano.

Monsoon strength affects global ice volumes, not vice versa?

Mon, 10 Sep 2018 11:41:06 -0400

New analysis of Chinese loess suggests rethinking of Milankovitch model

In the 1920s, Serbian scientist Milutin Milankovitch proposed that cyclical changes in Earth’s orbital eccentricity, as well as its axial tilt and orientation, shape global climate. Part of his theory — widely accepted since — is that the amount of solar radiation, or insolation, reaching high northern latitudes is a major factor in regulating global ice volume and albedo, which in turn control the strength of tropical monsoons. But in a new study, researchers suggest that instead of global ice volume regulating monsoon strength, it’s mostly the other way around.

Surfactants slow oceanic carbon dioxide uptake

Mon, 10 Sep 2018 11:28:54 -0400

Across the Atlantic Ocean, researches sampled the surfactant layer across several sites. Credit: Michael A. Orlando, CC BY-SA 3.0

The oceans are the largest long-term carbon sink on Earth, absorbing about a quarter of all anthropogenic carbon dioxide emissions. The rate of exchange of carbon dioxide between the oceans and the atmosphere is thought to be primarily controlled by wind-driven turbulence at the sea surface. More turbulence leads to increasing gas exchange and higher rates of carbon uptake by the ocean. But in a new study, published in Nature Geoscience, scientists found that biomolecules called surfactants floating at the sea surface may significantly reduce carbon dioxide exchange with the atmosphere — reducing the uptake of carbon dioxide by up to 50 percent. “As surface temperatures rise, so too do surfactants, which is why this is such a critical finding,” said lead author Ryan Pereira of Heriot-Watt University in Scotland in a statement.

Methane emissions offset some blue carbon burial benefits

Mon, 10 Sep 2018 09:34:39 -0400

A new study measuring emissions from tropical mangroves, like this one in Australia, suggests that the mangroves' methane emissions are higher than previously thought. Credit: Gentlefriends, CC BY-SA 4.0.

Wetlands are prolific sinks for atmospheric carbon. They pull carbon dioxide out of the air and sequester the carbon in plants, soils and sediments. But there’s a catch: Wetlands also emit methane, an even more potent, albeit far less abundant, greenhouse gas than carbon dioxide. Two new studies, one measuring methane emissions from a rehabilitated freshwater peatland in California and the other looking at emissions from tropical mangrove forests in Australia, are revealing that these so-called “blue carbon” sinks may emit much more methane than previously thought.

Sipping carbon-neutral fuel from the atmosphere

Mon, 10 Sep 2018 09:28:17 -0400

Carbon Engineering's proof-of-concept Direct Air Capture (DAC) plant in British Columbia has been harvesting carbon from the air since 2015. Credit: Carbon Engineering.

In the near future, vehicles may be powered by carbon that comes from the sky, rather than out of the ground. Direct Air Capture (DAC) technology pulls carbon dioxide out of the atmosphere and converts the carbon into pellets that can be used to make hydrocarbon fuel that works in traditional engines. A new study details the process, which has been tested over the last three years, and offers some cost-saving solutions that make DAC more economically feasible than ever.

Dry rivers secretly star in carbon cycle

Fri, 07 Sep 2018 11:13:22 -0400

Seasonal streams, like this creek in southern Grand Staircase-Escalante National Monument, may contribute far more carbon to the global carbon cycle than previously thought. Credit: Mary Caperton Morton.

In arid environments, some seasonal rivers and streams spend more time as dry riverbeds than they do as flowing waterways. A new study is giving scientists a clearer understanding of how these intermittently dry streambeds contribute to the global carbon cycle.

Geologic Column: Bone up on your spooky geo-vocabulary this Halloween

Fri, 07 Sep 2018 11:05:15 -0400

This list of Halloween-themed geo-jargon is full of fire and brimstone! Or at least brimstone, which of course is just sulfur. It's smelly, but not necessarily scary, unless you're climbing down a sulfur-lined slope toward a steaming volcanic fumarole like this person. Credit: Nadj91, public domain.

I’m hardly fanatical about Halloween, but I am an impassioned lover of puns and word humor (the more Dad-like, the better). So when it occurred to me I could crack open my copy of the American Geoscience Institute’s “Glossary of Geology” (GoG) to scour it for some of the eerier sounding jargon within, it seemed a perfect way to acknowledge the day. Fear not … unlike with H.P. Lovecraft’s “Necronomicon,” there are no ancient or evil powers to be conjured by speaking these ghastly glossary entries. You might, however, summon an appreciation for some of the fiendish creativity and ghoulish humor that’s gone into earth science’s vast lexicon.

Benchmarks: October 11, 1899: Second Boer War begins, fueled by discovery of gold

Fri, 07 Sep 2018 07:05:50 -0400

In the 1830s, in what is now South Africa, the Boers — farmers descended from Dutch settlers who bristled against British rule in the Cape Colony — began trekking farther inland into African tribal territory to find new land. Credit: painting by Charles Davidson Bell, 1898.

The 1886 discovery of gold on a farm in the Witwatersrand region of southern Africa drove the growth of Johannesburg, and gold mining has aided the South African economy for more than a century since. But gold, and diamonds, also fueled the Second Boer War, one of the most destructive armed conflicts in Africa’s history. The war resulted in the deaths of nearly 100,000 people, including tens of thousands of Boer women and children who died in British concentration camps. The consequences of the war, including gold mining’s lasting environmental legacy, and the rise of Afrikaner nationalism that reinforced apartheid, are still felt today.

Ocean tide size linked to supercontinent cycle

Thu, 06 Sep 2018 14:54:16 -0400

Daily tides are driven primarily by Earth’s rotation and the gravitational force of the moon on oceans. However, in a new study in Geophysical Research Letters, researchers suggest that tidal magnitudes are also influenced, on longer timescales, by the size and shape of the ocean basins, and are therefore driven by plate tectonics.

Down to Earth With: Volcanologist Thorvaldur Thordarson

Fri, 31 Aug 2018 20:17:56 -0400

Thordarson studies the 1995–96 eruption of Mount Ruapehu in New Zealand, where he witnessed the beginning phases of the eruption from a helicopter above the crater. Credit: courtesy of Thor Thordarson.

Despite growing up in Iceland, with Earth’s most volcanically active landscape as his playground, Thorvaldur Thordarson had no idea he would grow up to be a volcanologist. Nor did he suspect that his career path would take him all over the world to witness eruptions and aftermaths on six continents.

Getting There And Getting Around Rocky Mountain National Park

Fri, 31 Aug 2018 19:56:45 -0400

Each summer, the opening of Trail Ridge Road must wait until road crews manage to remove the snow drifts that blanketed the road during the previous winter. Credit: Terri Cook and Lon Abbott.

Denver (DEN) is the best arrival point for exploring Rocky Mountain National Park (RMNP), and a car is the most convenient way to see Trail Ridge Road and the park’s many other attractions. If you fly in, you can rent a vehicle at the airport and drive to Estes Park, the eastern gateway town, which is roughly 1.5 hours from the airport, or to Grand Lake at the west end of Trail Ridge, about a three-hour drive.

Travels in Geology: Roof of the Rockies: Trail Ridge Road

Fri, 31 Aug 2018 15:15:42 -0400

Driving Trail Ridge Road, North America's highest continuously paved highway, immerses you in the grandeur of the Rockies. Credit: Terri Cook and Lon Abbott.

In mid-April each year, two Colorado snow-clearing crews embark upon an assignment with a deceptively simple goal: to traverse the 77-kilometer stretch of road between them and meet at the middle. Armed with front-end loaders, graders and rotary plows, one team starts clearing snow on U.S. 34 in the town of Estes Park, Colo., while the other begins removing it from the same road in Grand Lake, Colo. Working in the lulls between fierce spring storms packing gale-force winds that frequently undo their efforts, the teams arduously ascend nearly 1,200 meters, clearing 3- to 6-meter-high snowdrifts in their path. When, after five to seven weeks, the crews finally come face to face near the crest of the Rockies, their success is heralded because it means that Trail Ridge Road, North America’s highest continuously paved route, is once again open for the summer.

Dutch Masters: The Netherlands exports flood-control expertise

Fri, 31 Aug 2018 14:56:20 -0400

The Netherlands has, for centuries, dealt with flooding and high waters by developing innovative water management techniques and technologies, and in recent years, other countries have been tapping this Dutch expertise. Here, the Maeslantkering, a massive moveable storm surge barrier that can be engaged to protect the city and port of Rotterdam from flooding, sits open, with its two swinging gates resting on dikes on either side of the Nieuwe Waterweg channel. The barrier, completed in 1997, was part of the last phase of the Netherlands' decades-long Delta Works project. Credit: shutterstock.com/GLF Media.

In early 2017, scientists from NOAA and other U.S. research institutions announced that new data had led them to raise the upper estimate of projected global sea-level rise by the end of this century to 2.5 meters. That’s considered the extreme scenario and would require a catastrophic melting of land-based ice sheets and glaciers in Greenland and Antarctica. However, it doesn’t take anywhere near that much sea-level rise to cause havoc. Global mean sea level has risen about 8 centimeters in the last 20 years, contributing to dramatic increases in coastal flooding. For example, nuisance flooding in U.S. coastal communities has increased by 300 to 900 percent in recent decades due to the increased intensity of storm surges, according to NOAA’s National Ocean Service. And it’s not just nuisance flooding that’s a problem.

Comment: Why is it so hard to teach climate change?

Fri, 31 Aug 2018 14:49:30 -0400

Climate science education often falls through the cracks in K–12 curricula. Earth and environmental science classes, in which climate science is most likely to be taught, are not required in most states. Thus, the incentive to teach those classes is absent. Credit: ©American Geosciences Institute, 2015.

Climate change was in the national spotlight this past summer when The New York Times Magazine devoted its entire Aug. 5, 2018, issue — except for the beloved puzzle section — to Nathaniel Rich’s article “Losing Earth: The Decade We Almost Stopped Climate Change.” As it happens, “Losing Earth” added a puzzle of its own. Late in his 30,000-word article, Rich wrote that he looked forward to the day when “the young will amass enough power to act” on climate change. But he neglected to ask whether they will have the knowledge to do so, in light of what is and isn’t being taught about the topic now.

Ice (Re)Cap: September 2018

Fri, 03 Aug 2018 13:43:20 -0400

A research camp on Pine Island Glacier, a major ice outlet for the West Antarctic Ice Sheet, which, a new study shows, lost 2.72 trillion metric tons of ice (plus or minus 1.3 trillion metric tons) between 1992 and 2017. Credit: U.S. Antarctic Program/photo by August Allen, NSF.

From Antarctica to the Arctic; from polar caps, permafrost and glaciers to ocean-rafted sea ice; and from burly bears to cold-loving microbes, fascinating science is found in every nook and crevasse of Earth’s cryosphere, and new findings are announced often. Here are a few of the latest updates.

European mammals will struggle under climate change

Fri, 03 Aug 2018 13:40:10 -0400

Roughly half of European mammals, including wolverines, could struggle to find new habitat amid changing climates. Credit: CC BY-SA 4.0, Jonathan Othén.

As temperatures on Earth rise, many animals have already begun migrating to more amenable climates, shifting their ranges. But not all animals will be able to relocate, according to a new study in the journal Diversity and Distributions.

Ancient DNA reveals diversity of Southeast Asia

Fri, 03 Aug 2018 13:35:30 -0400

Southeast Asia is one of the most genetically and linguistically diverse regions on Earth. New sequencing of ancient human DNA is helping scientists piece together the puzzle of how repeated influxes of hunter-gatherers and farmers to the area over the last 50,000 years created the high level of diversity seen today.

Mercury links Big Five extinction events

Fri, 03 Aug 2018 13:33:32 -0400

The locations of sites studied for mercury abundances are shown in yellow on this plate reconstruction from the time of the Frasnian-Famennian extinction. Credit: Racki et al., Geology, April 2018.

Mercury concentration spikes in the geologic record have been linked to massive volcanism in the form of large igneous provinces (LIP) such as the Deccan Traps, a kilometers-thick heap of basalt layers that formed in what is now India beginning late in the Cretaceous, and the Siberian Traps, an even larger mass of lava that erupted in Siberia at the end of the Permian. It’s thought that vast gas emissions associated with LIP eruptions could have significantly changed climate patterns and affected conditions such as ocean acidity. And four out of five of the most devastating extinction events of the last 550 million years have previously been linked, at least partly, to the formation of LIPs. A new study looking at mercury in rocks dating to the Late Devonian has now linked the fifth to volcanism as well.

Sunstones useful as Viking-era GPS

Fri, 03 Aug 2018 13:26:07 -0400

A piece of Iceland spar, a type of calcite that may have been used by Vikings to navigate in cloudy conditions. Credit: ArniEin, CC BY-SA 3.0.

The Vikings ruled the North Atlantic for hundreds of years without the benefits of magnetic compasses on the rough, often stormy waters. Legends have told of Vikings using sun compasses during clear weather and “sunstones” in cloudy conditions to navigate their weeks-long journeys between ports. A new study finds that sunstones made of calcite, cordierite or tourmaline may have indeed been accurate navigational tools.

New suspect emerges in theft of Earth's surface iron

Fri, 03 Aug 2018 13:23:12 -0400

Iron is the fourth-most common element in Earth’s crust, but why there isn’t more found near the surface in continental crust has been a long-standing question among geologists. In a new study, scientists implicate an overlooked mineral culprit in the theft of iron from continental crust: garnet. But not everybody is ready to exonerate the long-implicated magnetite.

Bolts of insight on earthly gamma ray showers

Fri, 03 Aug 2018 13:21:43 -0400

Surface detectors from the Telescope Array in Utah's western desert were used to detect gamma ray showers caused by lightning. Credit: John Matthews, University of Utah.

A handful of times between 2014 and 2016, an array of ground detectors placed in Utah’s western desert sensed something in thunderstorms that occasionally raged overhead: showers of gamma rays — the highest energy waves in the electromagnetic spectrum — occurring alongside lightning bolts. The observations, reported in a new study, mark the first time scientists spotted such gamma rays from the ground and reveal more about the relationship between lightning and gamma rays, potentially shedding light on some unanswered questions about lightning itself.

Gravity changes portended 2011 Tohoku earthquake

Fri, 03 Aug 2018 13:19:38 -0400

The tectonic setting of the 2011 Tohoku quake. Credit: K. Cantner, AGI.

A new analysis of satellite data has revealed a distinct change in the gravity signal measured across the Japanese archipelago starting several months before the March 11, 2011, magnitude-9.1 Tohoku-Oki earthquake — one of the largest seismic events in recorded history. The gravity change reflects interactions among shifting tectonic plates in the region, and its timing shortly before the earthquake raises the tantalizing notion that such signals could portend impending seismicity elsewhere. But researchers say it’s unclear if the signal seen in the new study is unique to the Tohoku quake or if it represents a phenomenon common to other large subduction zone quakes.

Great Barrier Reef has died and recovered before

Fri, 03 Aug 2018 13:12:45 -0400

The Great Barrier Reef has rebounded from die-off events many times; however, it has never faced the combination of threats that it does today. Credit: NASA.

It’s hard to imagine Earth without the Great Barrier Reef, yet with the threats confronting it — including ocean warming and acidification — its demise is a possibility marine scientists are studying. A new study of how sea-level rise and sedimentation have impacted the reef over the last 30,000 years, however, shows it might be more resilient than previously thought.

Down to Earth With: Volcanologist Scott Rowland

Fri, 03 Aug 2018 12:58:11 -0400

Volcanologist Scott Rowland, who studies Hawaiian lava flows and also works as a volcanologist on the Mars Curiosity Rover team, with the testbed rover at the Jet Propulsion Laboratory in Pasadena, Calif. Credit: Megan Kennedy-Wu.

Hawaii seems like an ideal place to nurture a budding volcanologist. Kilauea, on the Big Island, is one of the world’s most active volcanoes. And the terms used to describe the main types of basaltic lava flows — aa and pahoehoe — are Hawaiian words.

Geologic Column: "Collect Rocks Day" offers opportunity for inspiration

Fri, 03 Aug 2018 12:45:23 -0400

Photo by Fernando Reyes on Unsplash

I have been intrigued by rocks since I was a kid. In fact, as I write these lines I am surrounded by rocks I have collected over the years. On my window sill is a piece of shale containing several preserved ammonites, obsidian from Iceland, dolerite from Tasmania, and a sedimentary rock bearing fossilized sand ripples attesting to former currents along the western edge of the Western Interior Seaway, which stretched from the Gulf of Mexico to the Arctic during the late Mesozoic.

Travels in Geology: The pyramids of Giza: Wonders of an ancient world

Fri, 03 Aug 2018 12:25:25 -0400

The Pyramids of Giza, near Cairo, Egypt, are perhaps the most famous structures ever built. Credit: Terri Cook and Lon Abbott.

Few sights on our planet are as recognizable as Egypt’s Pyramids of Giza, the towering trio of monuments built to house the remains of three Old Kingdom pharaohs for all eternity. The pyramids are arguably the most famous human-made structures ever built, and their colossal scale, perfect symmetry and lofty perch on a plateau above the fertile Nile River Valley reflect the divine role that Ancient Egypt’s leaders held in both their lives and afterlives. For years we wanted to see these 4,500-year-old architectural and archaeological monuments but were reluctant to travel to Egypt during the social and political upheaval of the Arab Spring and its chaotic aftermath. Now with tourism there on the rise and hints of increasing stability, we decided it was finally time to view these ancient wonders for ourselves.

Getting There and Getting Around Cairo

Fri, 03 Aug 2018 12:23:25 -0400

An Egyptian woman bakes bread outside a Cairo restaurant. Credit: Terri Cook and Lon Abbott.

“Egypt’s main gateway is Cairo International Airport (CAI), which has nonstop flights to most major Middle Eastern and European cities. EgyptAir offers direct flights to Cairo from New York City and Toronto. From other North American locations, it’s usually most convenient to fly through Dubai, Abu Dhabi or a European hub. British Airways, Emirates, Etihad, Lufthansa and Turkish Airlines are among the carriers offering connecting service.

Science as a family affair

Fri, 03 Aug 2018 12:11:16 -0400

The Weiss family at the fall meeting of the American Geophysical Union (AGU) in December 2017 in New Orleans. From left to right: father Chad, Cameron, 15, Sean, 16, Ian, 13, Megan, 15, Evan, 15, and mother Nicola. Credit: Harvey Leifert.

Ian Weiss had already taken off his shoes and socks when he realized he’d left his lacrosse stick in the car one day in May 2015. He went to retrieve it, stepping barefoot onto the asphalt street outside his family’s Southern California home. “While opening the trunk I had to do the hot-feet dance on the pavement,” he recalls. It was a pivotal moment in more ways than one for Ian, then a sixth-grade student at Samuel E. Talbert Middle School in Huntington Beach, Calif.

Rivers in the sky: Improving predictions of atmospheric rivers to reduce risk

Fri, 03 Aug 2018 11:29:41 -0400

Atmospheric rivers are long, narrow weather systems that carry large amounts of moisture from the tropics into the midlatitudes. This NOAA illustration of a system stretching from the tropics around Hawaii to the U.S. West Coast, with darker blue shades representing greater amounts of precipitable water, depicts an atmospheric river that drenched Northern California in April 2018. Credit: NOAA National Environmental Satellite, Data, and Information Service.

In early February 2017, authorities in Northern California ordered more than 180,000 residents around the Oroville Dam to evacuate over concerns that heavy rains might cause the dam’s spillway to fail. The rains were brought by an atmospheric river (AR) — a long, narrow system of moist, tropical air that can deposit enormous amounts of water — adding to an already wet season for the U.S. West Coast. ARs occur around the planet, but certain regions — including western North America, where moisture from the tropics near Hawaii is repeatedly delivered by recurring “Pineapple Express” events — are especially prone.

Mineral Resource of the Month: Tin

Tue, 03 Jul 2018 16:27:19 -0400

By C. Schuyler Anderson, USGS mineral commodity specialist

PRODUCTION

GEOLOGIC OCCURENCE

The main source of tin is cassiterite (SnO2), a tin oxide mineral; cassiterite has been the primary source of tin throughout history. Most of the world’s identified tin resources occur as placer deposits, a large number of which are located along the Southeast Asian tin belt. The remaining resources occur as hydrothermal hard-rock veins. In the United States, tin deposits are rare; there are no known extensive tin placer deposits and the few hard-rock deposits are currently not economically exploitable.

Searching for the volcanic origins of iron ore

Tue, 03 Jul 2018 11:46:10 -0400

To replicate conditions inside magma chambers, samples were encapsulated in gold foil and subjected to temperatures up to 1,040 degrees Celsius and pressures up to a thousand times atmospheric pressure. Credit: ©Lennart A. Fischer.

Most iron ore comes from sedimentary deposits. However, a sizeable minority is mined from volcanic rocks, including those found along the Coastal Cordillera of northern Chile, and in Kiruna, Sweden.

Seismic waves are blind to water

Tue, 03 Jul 2018 11:42:26 -0400

Volcanic eruptions, like those at Alaska's Redoubt Volcano, can generate seismic waves that researchers use to interpret Earth's interior. Credit: U.S. Geological Survey.

Geoscientists use the seismic waves produced by earthquakes to image the internal structure of the planet. Some seismic waves travel through liquids, while others do not, which is how we know, for instance, that Earth has a solid inner core and a liquid outer core. Scientists had thought they could use these properties of seismic waves to image the distribution of water within the planet, mainly water within the crystal structures of rocks. But in a new study, researchers reveal that may not be the case.

A rocky source of nitrogen

Tue, 03 Jul 2018 11:38:51 -0400

Calculations of the planet’s nitrogen balance have always been off: plants and soils seem to sequester far more nitrogen than expected. The atmosphere has long been thought of as the only major source of nitrogen, but a new study indicates an additional source: as much as a quarter of Earth’s terrestrial nitrogen may be supplied by eroding bedrock.

Speartips point at south-to-north Clovis dispersal

Tue, 03 Jul 2018 11:35:35 -0400

Several routes have been proposed for the first human migrations into North America, with the most widely accepted suggesting a north-to-south traverse through an ice-free corridor east of the Rocky Mountains. But a new analysis of hundreds of spearpoints found across the western U.S. is turning this model on its head. Credit: map: K. Cantner, AGI; photo: Heather Smith.

During the last ice age, long before people first entered North America, much of the Canadian and American Rockies were buried under massive ice sheets. As the ice age waned about 13,000 years ago, an ice-free corridor 1,500-kilometers long and several hundred kilometers wide opened east of the Rocky Mountains.

Piecing together the puzzle of Pannotia

Tue, 03 Jul 2018 11:30:46 -0400

Researchers have found evidence that a supercontinent, Pannotia, existed between 650 million and 600 million years ago, forming after Rodinia and before Pangea. Credit: Nance and Murphy, Geological Society Special Publications, March 2018.

Earth’s landmasses have joined together into supercontinents and then split apart again as many as six times in the planet’s history. Pangea is the most famous supercontinent, but at least five pre-Pangean supercontinents — Rodinia, Columbia, Kenorland, Ur and Vaalbara — have been widely championed, mainly based on paleomagnetic data. Now, a new study offers a panoply of evidence for an often-overlooked supercontinent thought to have formed after Rodinia and before Pangea, called Pannotia, whose existence has long been in question.

Charting 500 years of Mississippi floods

Tue, 03 Jul 2018 11:27:45 -0400

The Mississippi River is notorious for flooding its muddy banks, with many critical areas actively managed by the Army Corps of Engineers to control flooding. But despite all the controls, major floods still occur. A new study looking at flood trends over the last 500 years suggests that manmade flood controls may be responsible for most of the increase in flood magnitudes on the river.

Cracking the temperature of columnar jointing

Tue, 03 Jul 2018 11:11:33 -0400

A new study found that columnar joints form at temperatures between 840 and 890 degrees Celsius. Credit: public domain/Patrice78500.

When molten rock cools and contracts, it sometimes cracks to form geometrically shaped columns. This process, called columnar jointing, has led to several famous geological structures, including Giant’s Causeway in Northern Ireland and Devils Postpile National Monument in California.

Mountaintops get less lonely for alpine plants

Tue, 03 Jul 2018 11:08:50 -0400

It takes a hardy plant to live on top of a mountain, but new research shows that summits in the Alps are hosting more species of plants than ever before. Long-term botany surveys conducted on 302 European mountaintops over the past 145 years show that the variety of plant species living on the harsh summits has markedly increased over the last 10 years due to climate change.

Geologic Column: The raw and the cooked

Tue, 03 Jul 2018 10:29:08 -0400

Credit: Pexels.com/pixabay; CC0 License.

Do you remember when we used to cook our veggies? It was before the French invented “La Nouvelle Cuisine” and had us eating everything raw like Homo erectus. No surprise, then, that it was a Frenchman, Claude Lévi-Strauss, who in 1964 published “The Raw and the Cooked,” a classic of anthropology. He proposed that opposites, such as raw and cooked, “drawn from everyday experience with the most basic sorts of things … can serve a people as conceptual tools for the formation of abstract notions and for combining these into propositions.” Well, all I know is that when we started eating our grub cooked rather than raw was a significant turning point in human history — though the real turning point was the control of fire. And H. erectus was the first to manage that.

Place-based education: Teaching geoscience in the context of location and culture

Mon, 02 Jul 2018 17:09:14 -0400

Arizona State University students participating in a place-based field trip near Round Rock in Arizona combined geological study with an exploration of indigenous and historic cultures of the Colorado Plateau. Credit: Steven Semken.

When geologist Kent Kirkby first joined the faculty in the University of Minnesota’s Department of Earth Sciences in 1994, he was assigned to teach a large, entry-level geoscience course that had last been revised in the 1970s. “While that revision had been very innovative for its time,” Kirkby says, “it was showing its age.” As he mulled options for redesigning the course, he learned through class surveys that less than 1 percent of the roughly 1,000 students who enrolled in it each year were considering a career related to earth science, and that it was also the last physical science class that more than three-quarters of the students intended to take. Given those statistics, “teaching the course as a traditional introductory science class made no sense,” he says.

Travels in Geology: From sea to sky in British Columbia

Mon, 02 Jul 2018 16:23:13 -0400

Last spring, while many Americans were migrating south in search of sunshine, our family headed north to rainy Vancouver, British Columbia, so our high school-age son could visit two colleges and we could all explore the city’s vibrant downtown. In addition to touring the campuses, he wanted to find out whether British Columbia’s magnificent mountains and captivating coastline would hold opportunities for outdoor activities during the misty “mud season.” What we learned is that, in this corner of southwest Canada, there’s no offseason for outdoor pursuits. Thanks to the region’s tremendous topography, which rises from sea to sky over just a few kilometers, what’s rain in the city falls as abundant snow high in the mountains, extending the winter sports season. In addition, kayaking and other water sports are enjoyed year-round, as is hiking — if you embrace the mud like the locals do. Ultimately, we discovered, there’s never a bad time to visit Vancouver.

Getting There And Getting Around Vancouver

Mon, 02 Jul 2018 16:04:20 -0400

“Most visitors to Vancouver and the surrounding area arrive via Vancouver International Airport (YVR) or by road, approaching the city from the east along the Trans-Canada Highway or from a U.S. border post to the south. Although flights into YVR are often good value, especially as a stopover for trans-Pacific flights, it’s often cheaper for U.S. travelers to fly into Seattle, as we did, and then drive across the border. Most rental car agencies permit travel between the two countries, but it’s important to verify this ahead of time. Although border formalities are usually quick and easy (as long as you remember to bring your passport), you should be prepared for queues lasting one to two hours.

Sea-level rise could cut off wastewater service to millions in U.S.

Thu, 21 Jun 2018 15:54:41 -0400

The Hyperion Water Reclamation Plant is the largest wastewater treatment plant serving the Los Angeles area. Coastal treatment plants in California and other states could be knocked out of service due to rising sea levels. Credit: Doc Searls, CC BY 2.0

Scientists report in a recent study that with just 30 centimeters of sea-level rise, roughly 4 million people in the U.S. could lose access to municipal wastewater services — services that allow three-quarters of America to run the tap and flush the toilet. And with even higher seas, the number goes up. The study, published in the journal Earth’s Future, is the first to analyze the resilience of the nation’s wastewater treatment plants to sea-level rise.

Travels in Geology: Kilauea: Experiencing Pele's wrath through the eyes of a young geologist

Tue, 12 Jun 2018 12:07:45 -0400

Kilauea's 3-kilometer-by-5-kilometer caldera sits in the middle of Hawaii Volcanoes National Park. The Halema`uma`u crater located within the caldera is currently erupting. Credit: ©iStockphoto.com/joeygil

This past summer, I lived a geologist’s dream: residing in a national park and getting up close and personal with Hawaii’s infamous Kilauea volcano. For hundreds of thousands of years, Hawaii’s Kilauea has been erupting on and off. But on Jan. 3, 1983, the volcano began one of its longest (and largest) eruptions, shooting a fountain of lava hundreds of meters into the air. Twenty-seven years later, the volcano is still alive and kicking — in fact, it’s the most active volcano in the world. For volcanologists, Kilauea is a mecca: an accessible active volcano in a picturesque location. So when I landed an opportunity to volunteer at the U.S. Geological Survey (USGS) Hawaiian Volcano Observatory near Kilauea, I couldn’t refuse.

Getting There and Getting Around Hawaii

Tue, 12 Jun 2018 11:52:42 -0400

The Big Island has two airports: Hilo on the east side (pictured here) and Kona on the west side. Credit: ©Shutterstock.com/Shawn Zhang

Many trips to Hawaii’s Big Island involve island-hopping. From the U.S. mainland, you’ll most likely fly through Honolulu on Oahu or Kahului on Maui on your way to either of the Big Island’s airports — Hilo on the east side or Kona on the west side. However, some airlines fly directly to Kona. Once on the Big Island, renting a car is your best bet for getting around because public transportation, albeit free, is virtually nonexistent: Buses run a handful of times a day during the week, but not at all on Sundays. From Hilo, getting to Hawaii Volcanoes National Park is a 30-minute drive straight up Highway 11. Getting to the park from Kona is more of a trek, a two- to four-hour scenic drive depending on which route you take.

The Sleeping Giants

Tue, 12 Jun 2018 11:48:18 -0400

The Big Island's tallest volcano, Mauna Kea, is home to astronomical observatories. Credit: Gro Birkefeldt

After you’ve gotten a taste of what Kilauea has to offer, consider taking the time to travel to the rest of the Big Island’s volcanoes.

Travels in Geology: To the top of Europe: Jungfrau, Switzerland

Tue, 12 Jun 2018 11:24:38 -0400

The 4,158-meter-tall Jungfrau in the Bernese Alps, part of the western Swiss Alps. Credit: ©Wengen-Muerren-Lauterbrunnental AG, www.swiss-image.ch

Intrepid visitors can take at least two paths to the top of Europe: an excruciating and dangerous ascent up the north face of the Eiger to the top of the nearly 4-kilometer-tall peak, or a comfortable (if steep) train ride through that mountain that allows less-athletic visitors to reach the neighboring Jungfrau.

Walking with Dinosaur Bones

Tue, 12 Jun 2018 11:14:04 -0400

If you need a dinosaur fix and you are visiting Zürich, take a half-day detour to the nearby Aathal Dinosaur Museum (www.sauriermuseum.ch). A quick train ride drops you in the small town of Aathal, about 500 meters from the historic textile factory that now houses the museum. A second-class daypass will get you there and back, as well as around the city and out to the airport, and costs about $22.

Making Jurassic Tracks in the Jura

Tue, 12 Jun 2018 11:11:29 -0400

Left and right: Dinosaur footprints at the Courtedoux tracksite in the Jura Mountains. Credit: courtesy of D. Marty, Paléontologie A16

Just to the north of the Swiss Alps, the gently sloping, lower-elevation Jura Mountains — namesake of the Jurassic — sprawl across the French-Swiss border and into Germany to the east. Composed of limestone and karst deposits, the low-lying mountains harbor caves and eroded cliffs, mountain chalets, Swiss watch factories — and dinosaur tracks.

Getting There And Getting Around Switzerland

Tue, 12 Jun 2018 11:09:22 -0400

Jungfrau and other peaks in the Bernese Alps are easily accessible by train or bus from Geneva or Zürich. The Swiss train system is excellent, and generally on time. Buses are reliable as well, run by Swiss Post (post office, bank and bus system, all in one, and all three are available from mountaintops to lakeshores, in all kinds of weather).

Travels in Geology: Up to Michigan's U.P.

Tue, 12 Jun 2018 10:51:50 -0400

Michigan's Upper Peninsula is a great place to view the colors of fall. Credit: ©iStockphoto.com/Bill Grove

Credit: AGI/NASA

You have to be tough to be a Yooper. Between the epic lake-effect snow, ship-sinking storms and summertime swarms of black flies, Michigan’s remote and rugged Upper Peninsula is one of the last true wild outposts in the lower 48 states. But while living in the U.P. may not be for everybody, a visit in any season will delight rock hounds, beachcombers, wildlife watchers, storm seekers and fall colors enthusiasts.

Getting There And Getting Around Michigan

Tue, 12 Jun 2018 10:40:33 -0400

Part of the Upper Peninsula’s appeal is its inaccessibility. The U.P. boasts a few small airports with service from Detroit and Chicago, but they have limited car rentals, so driving up from Michigan’s lower mitt or from Wisconsin or Ontario (across the Sault Ste. Marie International Bridge) is probably your best bet. Fortunately for travelers, much of the region’s economy is tourism-based and even the smallest waypoints offer cozy cabins and bed and breakfasts. Campsites are also plentiful throughout the U.P.

Travels in Geology: Clear water and cataclysm at Oregon's Crater Lake

Tue, 12 Jun 2018 10:21:56 -0400

Today, Crater Lake in southwestern Oregon is known for being one of the deepest, clearest lakes in the world. In 5,700 B.C., however, the scenery stunned witnesses for a very different reason: The eruption and collapse of Mount Mazama that created Crater Lake is thought to be one of the greatest geologic catastrophes ever witnessed by humans. A trip to Crater Lake National Park will not only redefine your concept of nature’s bluest blue, but it’s also an opportunity to bear witness to the peaceful aftermath of one of Earth’s great cataclysms.

Getting There And Getting Around Oregon

Tue, 12 Jun 2018 10:02:49 -0400

Crater Lake Lodge is open to summer visitors. Credit: ©Scott Catron, Creative Commons Attribution-ShareAlike 3.0 Unported

To visit Crater Lake, fly into Portland, rent a car and take a five-hour ride down Interstate 5 and a couple of smaller highways to Crater Lake National Park. If you’re not pressed for time, take scenic routes 26 and 97 along the crest of the Cascades mountain range, where you’ll pass by 3,426-meter-tall Mount Hood, 3,200-meter-tall Mount Jefferson and 2,375-meter-tall Mount Washington. The closest large towns to the park are Bend, a picturesque ski town in the shadow of the Three Sisters and Mount Bachelor volcanoes 180 kilometers north of the park, and Medford, a town with a small airport — with daily flights from Portland — in the Rogue River Valley 120 kilometers southwest of the park. Bend/Redmond also has an airport.

Travels in Geology: Lower Engadine Valley, Switzerland

Mon, 11 Jun 2018 16:55:35 -0400

A church in Scuol overlooks the Inn River. The mountains that loom over the Lower Engadine Valley were uplifted when the African Plate overthrusted the European continent more than 100 million years ago. Inset: One of the trails through the Lower Engadine Valley. Credit: ©Daniel Schwen, Creative Commons Attribution 2.5 Generic; inset: Naomi Lubick

Credit: AGI/NASA

Standing on the dark rocks beneath the small Swiss town of Scuol, you can look up into the surrounding chalk-white mountains and see the view from Europe to Africa. Or rather, you can gaze from the European continental rocks that pave the valley to the mountains above, which are made up of what was once the African Plate, before tectonic forces pushed it up and over the European continent.

Getting There And Getting Around Zürich

Mon, 11 Jun 2018 16:41:37 -0400

The Post Bus, operated by the Swiss National Post Office, is a convenient way to travel around the Lower Engadine Valley. Credit: swiss-image.ch/Christof Sonderegger

Most visitors to Scuol fly into Zürich, and either stay to check out the old yet modern cosmopolitan banking city or grab a train straight to the Lower Engadine Valley. A train ride to Scuol from Zürich’s main station (Hauptbahnhof in German) takes just under three hours, with a transfer at Landquart. The trip provides passengers with amazing views of the Swiss Alps. Check ZVV.ch or SBB.ch for fares and schedules. If you plan to continue traveling south by train, into Italy’s dolomites, consider buying a Eurailpass to save some money. Once you’re in Scuol, try the Post Bus for day trips.

Travels in Geology: Volcanoes, beaches and rainforests: Terrain hopping in Costa Rica

Mon, 11 Jun 2018 16:27:20 -0400

Arenal in Costa Rica is actively erupting. Night is a great time to see the volcano in action. Credit: right: ©iStockphoto.com/Rob Knight Inc; left: ©Scott Robinson, Creative Commons Attribution 2.0 Generic

Costa Rica is the happiest place on Earth, according to a 2009 survey by a London economic think tank. Credit the strong coffee and refreshing batidos — milkshakes with fresh banana, papaya, mango or some other tropical treat — and the country’s pura vida attitude that celebrates living life to the fullest.

Getting There and Getting Around Costa Rica

Mon, 11 Jun 2018 16:10:47 -0400

Many of Costa Rica's roads are unpaved, so renting a Jeep or other SUV is a good idea. Credit: ©iStockphoto.com/skodonnel

Most people traveling to Costa Rica fly into Juan Santamaría International Airport, outside of the capital of San José. The small city of Alajuela is actually closer to the airport, and some travelers stay there to avoid the capital’s congestion on their way into or out of the country. A second international airport in Liberia, in the northwest, allows for quicker access to the beaches of the Nicoya Peninsula. Visitors with lots of time and a sense of adventure can take the long drive from the United States, via the Pan-American Highway (called the Inter-American Highway in Central America).

Travels in Geology: Floods, Fires and Bears in Montana's Bitterroot Valley

Mon, 11 Jun 2018 15:51:32 -0400

Everything is big in Big Sky country: big mountains, big rivers, big glaciers, big floods and big bears. Montana itself is such a big place that it would take a lifetime to explore the whole state, so visitors are better off picking a few hot spots. Glacier National Park in far northern Montana may be the state’s most popular tourist destination, but Missoula and the Bitterroot Valley, a scenic four-hour drive south of the park, should also top any geo-traveler’s must-see list.

Getting There and Getting Around Montana

Mon, 11 Jun 2018 15:33:27 -0400

Rocky mountain oysters are a specialty in Montana and are celebrated at the annual Testicle Festival. Credit: Bottom to top: ©Vincent Diamante, Creative Commons Attribution-ShareAlike 2.0 Generic; Nancy Winn

Montana, the 41st state, shares a border with Canada to the north, Idaho and Washington to the west, Wyoming to the south, and North and South Dakota to the east. It’s not the easiest place in the United States to get to, but it’s well worth a trip.

Travels in Geology: Barbados: Ascending the sea-level staircase

Thu, 07 Jun 2018 17:12:06 -0400

Most people go to the Caribbean to escape — to relax on pristine beaches, enjoy fruity island drinks or perhaps swim with the dolphins. In Barbados, you can certainly do that. But in between your beach days, you may want to spend some time exploring the island’s unique geological features. The island provides the rare opportunities to stand on an active accretionary wedge and to visit uplifted coral reefs that have played a pivotal role in reconstructing climate and sea-level records of the recent geological past.

Getting There and Getting Around Barbados

Thu, 07 Jun 2018 16:57:35 -0400

Visitors to Barbados arrive at the Grantley Adams International Airport, on the south coast about 13 kilometers east of Bridgetown. Although there are established bus routes across the island, the most convenient way to explore it is by renting a car. A number of local agencies have depots at the airport. Driving is on the left in this former British colony.

Revealing the ancient sea levels recorded in reefs

Thu, 07 Jun 2018 16:55:32 -0400

Deriving the ancient sea levels in Barbados is easier than in other places, but still involves several steps.

First, researchers collect samples of the coral Acropora palmata, which only lives in the top five meters of the ocean, thus providing the tightest constraint on the elevation of sea level during its growth. Second, researchers date the coral via the uranium-thorium radiometric technique and measure its oxygen isotopic values so they can tie the data directly to the marine record of past global temperatures. Third, they survey the current elevation of each reef terrace.

Travels in Geology: Unearthing the ghosts of Ghost Ranch, New Mexico

Thu, 07 Jun 2018 15:40:02 -0400

For centuries, Ghost Ranch, N.M., was known as “Rancho de los Brujos” or Ranch of the Witches. Both monikers suit this stunning place well, as all sorts of creatures have left their bones behind here in the 400-meter-high cliffs layered with red, yellow and white Mesozoic rocks.

Get Dirty

Thu, 07 Jun 2018 15:07:38 -0400

If hiking the trails at Ghost Ranch and perusing the museums aren’t hands-on enough for you, consider signing up for a course through the Ghost Ranch Education Center, which offers reasonably priced (about $300 a week) one- and two-week classes throughout the year.

Getting There and Getting Around Albuquerque

Thu, 07 Jun 2018 14:49:29 -0400

To get to Ghost Ranch, fly into Albuquerque or Santa Fe, rent a car and drive north on Highway 84 past Española and Abiquiu to Ghost Ranch. A sign marks the right-hand turn into the Ghost Ranch Education and Conference Center between mileposts 224 and 225. The museums and visitor center are approximately 1.5 kilometers off the paved highway on a dirt road suitable for all cars.

Travels in Geology: The Burren: Ireland's "Great Rock" Region

Thu, 07 Jun 2018 14:30:22 -0400

The Burren in western Ireland is one of the largest karst landscapes in Europe. Credit: ©Shutterstock.com/Pyma

The Burren — one of the largest karst landscapes in Europe — is a land of contradictions. In 1651, an English army officer noted that this region on Ireland’s west coast “is a country where there is not water enough to drown a man, wood enough to hang one, nor earth enough to bury him. This last is so scarce that the inhabitants steal it from one another and yet their cattle are very fat. The grass grows in tufts of earth of two or three foot square, which lies between the limestone rocks and is very sweet and nourishing.”

Getting There and Getting Around the Burren

Thu, 07 Jun 2018 14:19:35 -0400

If you’re in Ireland, the Burren is definitely worth a visit. The Burren’s nearest airport is Shannon Airport, approximately a 45-minute drive away. The trip from Dublin is a four-hour drive. Renting a car is the best way to explore the region in depth. But keep in mind that the roads are narrower than you might presume, and visitors often underestimate how long journeys can take. (Keep in mind also that in Ireland, like in England, you drive on the left side of the road.)

Travels in Geology: Nova Scotia: A driving tour of Pangaea

Thu, 07 Jun 2018 13:59:54 -0400

What’s the quickest way to see the Scottish Highlands and Africa? Take a trip to Nova Scotia. The southeastern Canadian province is a mash-up of continental fragments whose landscape testifies to the power of glacial and tidal forces. Slightly smaller than West Virginia, the province is easy to get around and is packed with geological sites without being overwhelming.

Getting There and Getting Around Nova Scotia

Thu, 07 Jun 2018 13:50:53 -0400

Getting to Nova Scotia is easy by plane, car or ferry. Most flights arrive in Halifax, roughly in the middle of the province. If you’re driving from the United States, take New Brunswick Route One from the Maine border to meet up with the Trans-Canada Highway, which meanders through the province; however, it’s an eight-hour trip from Bangor, Maine, to Halifax and there’s not a lot to do or see along the way. A shorter route is to take the car ferry that sails from Saint John, New Brunswick, to Digby, on Nova Scotia’s northwestern coast. It takes a few hours, but there are several trips daily and it beats having to drive all the way around the Bay of Fundy.

Travels in Geology: Australia's Blue Mountains Delight the Senses

Thu, 07 Jun 2018 13:32:35 -0400

The Three Sisters formation, a triplet of sandstone peaks, as seen from a cable car descending into Jamison Valley. The Blue Mountains get their name from the blue haze that drapes the region. The mist is made up of oil droplets from eucalyptus trees. Credit: ©Meghan Miner

Credit: ©Hector Garcia, Creative Commons Attribution-ShareAlike 2.0 Generic

Australia has a lot to offer when it comes to geology, but you don’t have to venture as far inland as the famed Ayers Rock to see spectacular sights. Sydneysiders have been seeking respite from urban chaos in the nearby Blue Mountains National Park for almost a hundred years. The mountains are known for their sweeping vistas, cool microclimate, wildlife, Aboriginal history and rock formations like the statuesque Three Sisters and the rubble heap of Ruined Castle.

Getting There and Getting Around The Blue Mountains National Park

Thu, 07 Jun 2018 13:16:46 -0400

The Blue Mountains National Park is about 100 kilometers west of Sydney. It is accessible by highway via the M4 Motorway and the Great Western Highway to the gateway towns of Leura, Wentworth Falls and Katoomba. Double-decker trains also run from 4 a.m. to midnight daily from Sydney’s Central Railway Station, stopping in the major mountain towns. Sydney’s international airport is connected directly to the train station by a rail line built in 2001. Alternatively, several bus or “coach” companies offer trips or tours of the Blue Mountains region from Sydney; tickets and information can be found in the kiosks along Circular Quay on Sydney’s harbor. Once you’re in the Blue Mountains region, it’s easiest to get around on foot. The trails are a short walk from most of the downtown areas, and, should you feel like switching towns, the rails are the easiest link between them.

Travels in Geology: Florissant fossil beds: An Eocene time capsule

Thu, 07 Jun 2018 13:08:51 -0400

Beneath the grassy meadows and pine-studded hills of central Colorado lies one of the richest and most diverse fossil deposits in the world. From enormous petrified redwood stumps to the individual lenses in a fly’s compound eye, an entire ecosystem of rarely preserved life forms has been fortuitously fossilized, narrating the story of a warmer and wetter prehistoric Colorado that thrived at the brink of a dramatic episode of global cooling.

Getting There and Getting Around Colorado Springs

Thu, 07 Jun 2018 13:01:38 -0400

Colorado Springs is a good jumping off point for exploring Florissant Fossil Beds National Monument. A car is necessary to get around the area; you can rent one at the Colorado Springs Airport if you choose to fly into Colorado. Once you’re ready to visit the fossils, head west on Highway 24 for about 50 kilometers to the town of Florissant, where you’ll find gas, a couple of restaurants and convenience stores. Woodland Park, about 25 kilometers east of Florissant, offers accommodations and more eating options.

Travels in Geology: Soaking up the Dead Sea: A trip to Israel's salty sea is a geological and historical delight

Thu, 07 Jun 2018 12:49:10 -0400

Salt formations rise up from the Dead Sea. Credit: ©iStockphoto.com/Irina Opachevsky

Almost anywhere you turn in Israel, you’re bound to find fascinating geology or the remnants of ancient human history. Some of the best of both can be found where you might least expect it — near the Dead Sea, one of the least hospitable places on Earth. Located in the western Judean Desert on the border between Israel and Jordan, the sea is an artifact of incredible tectonic activity, which also birthed the jagged mountains that surround one of the world’s saltiest bodies of water.

Getting There and Getting Around Israel

Thu, 07 Jun 2018 12:45:50 -0400

A Dead Sea resort. Credit: ©Shutterstock.com/photostockar

Flights from the United States to Israel arrive in Tel Aviv, a cosmopolitan resort city known for its restaurants, clubs and beaches roughly in the middle of Israel’s Mediterranean coast. From there it is a two-hour drive to the Dead Sea. Renting a car at the airport is the easiest way to get around, but taxis will also take you there. From Jerusalem, you can also catch a bus to the Dead Sea from the central bus station.

The Destruction of Sodom and Gomorrah: Earthquakes or Volcanoes?

Thu, 07 Jun 2018 12:35:35 -0400

This salt pillar on Mount Sodom is nicknamed Lot's Wife, a reference to the biblical story of the destruction of Sodom and Gomorrah. Credit: ©iStockphoto.com/Сергей Пономарев

The name of the Dead Sea’s Mount Sodom comes from the biblical story of Sodom and Gomorrah. The Old Testament says God destroyed the cities with fire and “flaming smoke” for the sins of their inhabitants. God allowed Lot and his family to flee the destruction. But Lot’s wife disobeyed God’s orders and was turned into a pillar of salt. Mount Sodom is made almost entirely of halite — sodium chloride — and among the formations near the Dead Sea is a pillar known as Lot’s Wife.

Travels in Geology: Ever-Changing Turkey

Thu, 07 Jun 2018 12:21:51 -0400

Left: The Hagia Sophia was built as a cathedral in A.D. 532 during the Byzantine Empire. In 1453, the Ottomans turned it into a mosque. Today it is a museum. Right: The Basilica Cistern is a subterranean reservoir that dates to the sixth century A.D. It is supported by more than 300 marble columns, including this one carved into the shape of Medusa's head. Credit: right: ©iStockphoto.com/Burcin Tuncer; left: ©iStockphoto.com/oytun karadayi

The Greek philosopher Heraclitus famously quipped that “change is the only constant.” Few places on Earth are as emblematic of change, both geological and historical, as the Republic of Turkey.

Getting There, Getting Around and Getting Informed

Thu, 07 Jun 2018 12:04:31 -0400

Istanbul and Ankara, Turkey’s capital, are both easy to fly to from the United States. Within Turkey, most travelers opt for the inexpensive but well-developed bus system, including overnight routes that take you from one part of the country to another while you sleep. (I recommend bringing earplugs and a sleep mask if you actually want to get some sleep.)

Travels in Geology: Mallorca set in stone

Wed, 06 Jun 2018 13:51:15 -0400

This cloverleaf turn on the winding road down to the mouth of Mallorca's Torrent de Pareis is empty in the off-season. During the tourist season, the road is clogged with visitors who are eager to explore the island's geological history. Credit: Naomi Lubick

Credit: AGI/NASA

A spring walk along Mallorca’s northern coast yields views of sawgrass, peppered with tiny flowers just beginning to bloom in mauve and white. The stunning blue of the Mediterranean stretches to the horizon, away from the steeply rolling slopes of grass and craggy outcrops. The shore lies several hundred meters below the well-groomed walking trail, and if there is sun shining through coastal clouds, it promises a warmer afternoon after crisp, cool evenings and chilly nights.

Getting There and Getting Around Mallorca

Wed, 06 Jun 2018 13:32:32 -0400

A view of Palma de Mallorca's coast. Credit: Naomi Lubick

To get to Mallorca, you can fly from many major airports in Europe on a one- to two-hour flight. If you have the time (and perhaps already plan to have a car during a trip in mainland Spain), you can also take a ferry. Going from Barcelona to Palma de Mallorca with your car can cost the same as a plane ticket on an average airline carrier, about $350 — but it’s a seven-hour trip to cover a few hundred kilometers.

Travels in Geology: Exploring Vulcan's Playground: The Volcanoes of Southern Italy and the Aeolian Islands

Wed, 06 Jun 2018 12:35:11 -0400

The prospect of traveling to Italy might conjure romantic thoughts of stucco-covered villas surrounded by terraced vineyards, ancient visages carved in marble, fountains gurgling in cobblestone piazzas, and pasta smothered in tomato and basil. However, when I was asked to spend a semester teaching in northern Italy, these were not my first thoughts. As a geologist, I instead pondered the Dolomites in alpenglow, the exposure of the iridium-bearing Cretaceous-Paleogene boundary (formerly known as the K/T) in Gubio, and the possibility of visiting some of Italy’s famous volcanoes — Mount Vesuvius and Mount Etna — to the south.

Getting There and Getting Around Sicily

Wed, 06 Jun 2018 12:26:57 -0400

Italy’s volcanoes are mostly in the south, so flying into Rome or Naples is probably easiest. Getting around Italy is also very easy, whether you take the train or rent a car.

To get to Sicily and Mount Etna, you can take a puddle-jumper flight from most airports in Italy into Palermo or Catania or take a ferry from several locations, including Naples and just outside of Rome. Getting around Sicily is a bit more difficult than the mainland, but relatively easy via bus or train, especially if you plan ahead and aren’t traveling on a major holiday when many stations shut down. Getting to more remote locations is easiest if you rent a car, but beware that driving on Sicily can be dangerous. If you book a volcano tour, such as through Volcano Trek or Volcano Discovery, your travel arrangements will be made for you.

Travels in Geology: The desert geology of Namibia: A writer and her father explore otherworldly dunes, oases and meteorites

Wed, 06 Jun 2018 12:14:29 -0400

Any minute now a giant sandworm will burst out of the ground and devour me, I thought as I collapsed on the sand. Just like in Frank Herbert’s book, “Dune,” about an alien desert planet.

Getting There and Getting Around Namibia

Wed, 06 Jun 2018 11:50:10 -0400

The best time to visit Namibia is in the dry season, from April to December. In particular, the dry season offers the best game-viewing in Etosha National Park. Water scarcity draws the animals to the park’s springs.

The Skeleton Coast

Wed, 06 Jun 2018 11:47:14 -0400

The Skeleton Coast, part of the Namib Desert, is named for the whale bones and the hundreds of broken ships that litter its beaches. Many a sailor lost his life after being run aground in the Skeleton Coast’s thick fog. Those who made it to land often succumbed to starvation and exposure in the coast’s harsh climate.

Travels in Geology: Touring geologic time in Colorado Springs

Wed, 06 Jun 2018 11:06:47 -0400

Few visitors to Colorado Springs, Colo., realize that the spectacular scenery on display at famous sites like Pikes Peak, Garden of the Gods, and the campus of the U.S. Air Force Academy is largely the result of varied geologic processes spanning more than a billion years. Pioneering 19th-century geologist Ferdinand Vandeveer Hayden summed it up best when he said: “I do not know of any portion of the West where there is so much variety displayed in the geology as within a space of 10 miles square around Colorado [Springs].” In fact, the city holds the rare distinction of hosting rocks from every geologic time period save one. The presence of this unusually complete rock history means that while enjoying Colorado Springs’ premier attractions, you can also take a tour of the geologic timescale.

Getting There and Getting Around Colorado

Wed, 06 Jun 2018 10:54:42 -0400

Colorado Springs is easily accessible via major roads or by air. Although the city suffered a devastating wildfire this summer, none of its primary tourist attractions were burned, and all are open for business.

The town is well equipped with hotels, restaurants, tours and everything else a traveler could need. Your one-stop shop for area maps showing all the attractions listed here, lodging, food and activities, not to mention coupons, is the city’s helpful tourist website www.visitcos.com.

Travels in Geology: South Africa on safari for the geological Big Five

Wed, 06 Jun 2018 10:40:04 -0400

Credit: AGI/NASA

South Africa is hard to beat when it comes to diversity of nature. Whether we are talking about the country’s charismatic megafauna, its marine ecosystem, the unique fynbos plant community, or the extraordinary rock record, South Africa has something for everyone.

Getting There and Getting Around South Africa

Wed, 06 Jun 2018 10:27:30 -0400

Table Mountain provides a dramatic backdrop to Cape Town. Credit: ©iStockphoto.com/Hongqi Zhang

Getting to South Africa is going to set you back a pretty penny. Our airline tickets cost about $2,000 each, for coach. It’s a very long flight, so you may as well commit to several weeks in country to make it worthwhile. We broke the journey up by taking advantage of a 10-hour layover at London’s Heathrow airport by going downtown to see the Rosetta Stone and pay our respects to Charles Darwin and Charles Lyell, who are interred near one another at Westminster Abbey.

Travels in Geology: Lake Tahoe Jewel of the Sierra Nevada

Wed, 06 Jun 2018 10:09:01 -0400

Lake Tahoe's famed water clarity has been clouded in recent years by increased algal growth due to nutrient runoff. Credit: ©Mary Caperton Morton

With a rich geological and cultural history, and ample hiking, camping and sightseeing opportunities, Lake Tahoe is one of most popular vacation destinations in the United States. The lake straddles the California-Nevada border at an elevation of 1,900 meters, occupying an intermontane basin rimmed by the towering peaks of the Sierra Nevada, including the two highest peaks in the basin, Freel Peak and Jobs Sister, each with an elevation of approximately 3,300 meters.

Getting There and Getting Around Nevada

Wed, 06 Jun 2018 09:52:46 -0400

Getting to Lake Tahoe from the major airports in Sacramento, Calif., and Reno, Nev., is fairly easy. From Sacramento, it is about a two-hour drive along scenic Interstate 80 or U.S. 50. Interstate 80, which takes visitors to the northern part of Lake Tahoe, is a bit of a longer but easier drive and it passes the Donner Memorial State Park. The park — which commemorates the emigrants from the East to California in the mid-1800s, including the famed Donner Party, many of whom perished in the winter of 1846-1847 — offers recreational opportunities in the summer and winter. U.S. 50 is a slightly shorter but windier drive that goes through California gold country and ends up at South Lake Tahoe, a city with lots of casinos and ample beaches and recreational activities. From Reno, Lake Tahoe can be reached in less than an hour via Interstate 80 and the Mount Rose Highway. All roads to Lake Tahoe are open year round, with only temporary closures during times of very heavy rain or snowfall. A few local public side roads such as Fallen Leaf Lake Road and Blackwood Canyon Roads are not plowed in the winter.

Ice (Re)Cap: July 2018

Tue, 05 Jun 2018 17:08:53 -0400

The icebreaker CCGS Amundsen breaks a path through the Arctic in October 2010. Credit: Canadian Coast Guard, CC BY-ND 2.0.

Diamonds reveal water in deep mantle

Tue, 05 Jun 2018 17:05:30 -0400

A new study analyzing the structural and chemical properties of diamonds from various locations in Africa and China found inclusions of ice-VII, a form of crystallized water created under very high pressure that has never before been found in nature. Credit: Marilyn Chung/Berkeley Lab.

Inclusions in diamonds often render them undesirable to consumers, but they can provide researchers with striking insights into Earth’s composition. Recently, scientists probing diamond samples for the presence of carbon dioxide stumbled instead upon inclusions of ice-VII — a type of crystallized water that forms at very high pressures, and has never before been found in nature.

Trio of studies track stone tool technology in Kenya

Tue, 05 Jun 2018 17:02:59 -0400

About 300,000 years ago, East Africa was a hotbed of human evolution and innovation. Sweeping ecological changes contributed to the emergence of modern humans, and spurred the first long-distance trade routes and novel toolmaking technologies. Three new studies published in Science shine a spotlight on Kenya’s Olorgesailie Basin, where the clunkier Acheulean tool technology gave way to the smaller, sleeker Middle Stone Age tool technology famously associated with Homo sapiens.

Did a massive eruption spur Christianity in Iceland?

Tue, 05 Jun 2018 16:54:17 -0400

The landscape and culture of Iceland, more so than any other country, have been shaped by volcanism. In a new study, researchers have refined the dates for the massive 10th-century Eldgjá eruption, which occurred just a few decades after the island was first settled. The findings may support a connection between the violent volcanism depicted in Iceland’s most celebrated medieval poem and the island’s conversion from paganism to Christianity.

Weedy seeds gathered in once-green Sahara

Tue, 05 Jun 2018 16:36:57 -0400

Today, the vast and arid Sahara Desert seems an unlikely place to find early signs of seed gathering and plant cultivation in Africa, but new evidence shows that, 10,000 years ago, people were collecting, sorting and saving seeds near a rock shelter known as Takarkori.

Yellowstone's Mexican mantle plume

Tue, 05 Jun 2018 16:30:18 -0400

Yellowstone's many thermal features are fueled by a deep mantle plume rooted at the core-mantle boundary under Mexico. Credit: Nelson et al., Nature Geoscience, 2018.

The volcanic activity at Yellowstone National Park is impressive, with thousands of active thermal features dotting a nearly 4,000-square-kilometer caldera. Scientists have long suspected that a massive mantle plume underlies the supervolcano. Now, new imaging has provided the clearest picture yet of the heat source that drives Yellowstone’s volcanism.

Rolling thunder portends remote eruptions

Tue, 05 Jun 2018 16:25:05 -0400

Researchers detected volcanic thunder from two eruptions of Bogoslof Volcano, a predominantly submarine stratovolcano that breaches the ocean surface north of Alaska's Aleutian Islands. Credit: K. Cantner, AGI.

The logistics of monitoring volcanoes located in remote regions, such as Alaska’s Fox Islands, can be prohibitive — but monitoring is necessary, as ash clouds billowing from even far-flung volcanoes can make their way into airplane flight paths. Researchers are now proposing an acoustic warning system to detect volcanic ash clouds that would rely on listening for the thunderclaps that often herald these eruptions.

India's urban areas punch city-shaped holes in fog

Tue, 05 Jun 2018 16:20:14 -0400

Widespread fog blankets northern India in this image captured by the Moderate Resolution Imaging Spectroradiometer on NASA's Terra satellite on Dec. 7, 2016. Fog holes over several major cities are visible. Credit: NASA.

Air pollution boosts fog formation in some places, creating whiteouts that can affect air and ground transportation, air quality, and public health. In northern and eastern India, persistent fog often hovers over the Indo-Gangetic Plain, a vast region dotted with several densely populated cities, including Delhi, home to 19 million people. Over some of these cities, however, satellite imagery is revealing large holes in the fog.

Cretaceous volcanic ash seeded U.S. oilfields

Tue, 05 Jun 2018 16:15:52 -0400

A new study using samples from this outcrop — exposing the contact between the Cretaceous Eagle Ford Shale and Austin Chalk formations near Osman Canyon, Texas — suggests the abundant oilfields of the western United States may owe their existence to Cretaceous volcanic ash. Credit: Cin-Ty Lee.

Petroleum and natural gas stores are often found amid rocks — particularly ashbeds — deposited during the Cretaceous, when dinosaurs roamed Earth and abundant volcanic arcs lined the edges of the continents.

Comment: The changing shape of local climates

Tue, 05 Jun 2018 15:51:54 -0400

Figure 1. These cumulative distribution functions (CDF) represent the probability (P) of the maximum summer daytime temperature (T) around Bordeaux, France, being below a given temperature on the x-axis for the years 1950-1959 (orange) and 1993-2001 (blue). The separation between the two curves indicates a change in local climate between the two nine-year periods. For instance, median summer days (probability of 50 percent) warmed about 2 degrees Celsius (horizontal black bar), while the probability of the maximum temperature being below 28 degrees decreased from 83 to 66 percent (vertical black bar). Note that warmer days generally warmed more than cooler days (though the effect decreases for very hot days), indicating a change in the overall shape of the distribution rather than a consistent increase in temperature for all types of days. Credit: K. Cantner, AGI; data courtesy of David Stainforth.

Earth’s climate is changing. Increasing atmospheric greenhouse gas levels inevitably result in more heat being trapped in the lower atmosphere, the oceans and the land surface. But what does that mean where you are? What are the local consequences of global climate change? And what are the implications for decisions about how to adapt — decisions related to building design or flood protection measures, for example?

Geologic Column: Tarnish on the Golden State

Tue, 05 Jun 2018 15:29:43 -0400

Credit: Jamie McInall, public domain

For the 10th straight year, my wife, Claudia, and I were “California Snowbirds” last winter, leaving our snow shovels behind in Virginia for the good life in Southern California. While the winter sun there remains wonderful, California is changing.

Getting there and getting around England

Tue, 05 Jun 2018 14:17:00 -0400

From North America, the cheapest and most convenient access to the Jurassic Coast is via one of London’s major airports. Nonstop service to Heathrow (LHR) and Gatwick (LGW) airports is available from many major U.S. cities.From London, the easiest way to get to (and around) the Jurassic Coast is by renting a vehicle, assuming you’re comfortable driving on the left side of the road. Because Gatwick is located on London’s southern outskirts, it offers the best escape to England’s southern coast from the hustle and bustle of the city. National Express offers convenient and inexpensive bus shuttles between Heathrow and Gatwick. You can also catch a quick flight to Bournemouth or Exeter and either rent a vehicle or hop aboard a bus traveling one of the five routes that regularly ply the southwest coast. It’s also possible to reach the area via rail. If you decide to rent a vehicle, any airport will offer a good selection of international and local carriers.

Travels in Geology: Trapped by geology in Iceland with flights grounded by volcanic ash, one writer seeks out the island's geologic wonders

Tue, 05 Jun 2018 13:23:08 -0400

With plentiful precipitation and glacial meltwater, Iceland is famous for its abundance of waterfalls, including Hraunfossar. Credit: David B. Williams

On a recent trip to Iceland, my wife and I learned a central fact of life while traveling around this isolated island country: We could never escape the geology. We quickly learned to be wary of hot water taps because the water — sourced directly from geothermal hot springs — came out at scalding temperatures. At a hostel in the small town of Laugarvatn, we more comfortably exploited this phenomenon by soaking in a hot pot — similar to one built by one of Iceland’s most famous early citizens, the 12th-century writer Snorri Sturluson, which you can still visit. We also ate delicious tomatoes grown in greenhouses heated by Iceland’s largest thermal spring, which gushes 180 liters of boiling water every second.

Getting There and Getting Around Iceland

Tue, 05 Jun 2018 12:47:35 -0400

Iceland Air is the main airline serving Iceland, but many major American and international carriers stop there. The airport is in Keflavik, about 50 kilometers from the capital city of Reykjavik. Public buses timed to flight arrivals run to and from Reykjavik.

Off the beaten path in the north of Iceland

Tue, 05 Jun 2018 12:44:01 -0400

Although many of Iceland’s best-known geologic features are in the south — on the southwest Reykjanes peninsula, near Keflavik airport and the capital city of Reykjavik, and along the southern coast Ring Road — the north shouldn’t be overlooked. Without entering the interior highlands, which often requires four-wheel-drive, one can skirt the border of Vatnajökull National Park to take in an array of sights from geothermal to glacial.

Travels in Geology: Northeastern Australia's Atherton Tablelands young volcanoes, waterfalls and rainforest near the Great Barrier Reef

Tue, 05 Jun 2018 12:12:32 -0400

Little Millstream Falls near Ravenshoe, Atherton Tablelands, North Queensland, Australia. Credit: ©Shutterstock.com/Ralph Loesche

Just one breathtaking hour’s drive from Cairns, the gateway to the Great Barrier Reef on the coast of Queensland, in northeastern Australia, the scenic Atherton Tablelands, with their young volcanoes, dramatic waterfalls and lush rainforest, rise a thousand meters above the humid coastal plain. On a leisurely day trip you can circumnavigate this nearly flat plateau, soaking up the scenery formed by some of the continent’s youngest volcanoes, ambling through threatened rainforest ecosystems, and sampling exotic tropical produce.

Getting There and Getting Around Cairns

Tue, 05 Jun 2018 11:47:25 -0400

Unusual animals can be seen at the Great Barrier Reef and wandering the backroads of the Atherton Tablelands. Credit: ©Shutterstock.com/Ralph Loesche

Most visitors fly to Cairns, a tourist-oriented city of 124,000 people with a huge range of restaurants, services and accommodations, including two campgrounds. Several companies run bus tours from Cairns to the Tablelands, but it’s most convenient to rent a car from one of the many airport rental agencies and drive yourself. Just remember to drive on the left side of the road.

Travels in Geology: Santorini: Dangerous volcano, postcard-perfect jewel of the Aegean

Tue, 05 Jun 2018 11:21:02 -0400

Santorini is an idyllic Greek isle renowned for its sensational sunsets, colorful beaches, and blue-domed, whitewashed buildings clinging to sheer, dark cliffs. Located in the Aegean Sea, this unique destination is part of a circular archipelago of volcanic islands that were joined together in a single land mass until about 1600 B.C., when it was ripped apart in one of the largest volcanic eruptions in recorded history.

Getting There and Getting Around Greece

Tue, 05 Jun 2018 10:59:22 -0400

A stay on Santorini is not complete without watching the sun set over the Aegean from Phira, Oia, Firostefani or Imerovigli. Credit: Megan Sever

Reaching Santorini by one of the regular domestic or chartered international flights is convenient, but to appreciate fully the dramatic caldera, we recommend arriving by slow ferry (with observation decks). Several are available each day from Athens’ port, Piraeus, as well as more sporadically from other islands. Santorini is very compact, so you can stay on any coast and still see all of the attractions. Although there are established bus routes, the most convenient way to explore the island is by renting a car, motorbike or ATV in any of the main towns.

Getting There and Getting Around Chile

Tue, 05 Jun 2018 10:38:44 -0400

You can arrive in Arica through a few different channels. The easiest is to fly to Santiago and then Arica with a short stop in Iquique; there are daily flights on LanChile and Sky Airlines. A more adventurous option is to fly into Tacna, Peru, and take either a “collective,” or shared ride, a taxi or the Ferrocarril Tacna-Arica train south to Arica.

Travels in Geology: Chile: Exploring the archaeology, volcanoes and hot springs of the northern Atacama Desert

Tue, 05 Jun 2018 10:36:00 -0400

Credit: AGI/NASA

Mention the Atacama Desert and many people likely imagine an ocean of sand where rain never falls and life faces insurmountably hostile conditions. This is, after all, where scientists go to study Mars. Although some regions of the Atacama are indeed stark and barren, the northern section of this vast desert, which stretches approximately 965 kilometers along the western edge of Chile, contains diverse ecosystems, a rich archaeological history and, of course, intriguing geologic features.

Travels in Geology: Going to extremes in Death Valley

Mon, 04 Jun 2018 17:08:13 -0400

The Dante's View overlook on the crest of the Black Mountains is the best bird's-eye view of Death Valley, short of climbing the 3,367-meter-tall Telescope Peak across the valley. Credit: Mary Caperton Morton

A desert called Death Valley sounds like a place to avoid. Don’t let the ominous name scare you away. Most of the year, this vast and rugged expanse of eastern California is brutally hot, but visit in winter or early spring and you’ll find a surprisingly beautiful and vibrant place.

Getting There and Getting Around California

Mon, 04 Jun 2018 16:50:35 -0400

Due west from Death Valley are California's Sierra Nevada mountains, including Mount Whitney, the highest point in the lower 48 states, seen here on the left. Credit: Mary Caperton Morton

One of the easiest ways to visit Death Valley is to fly into Las Vegas, rent a car with four-wheel drive and head due west 250 kilometers to the east entrance of the park. Before exploring, stop at the Furnace Creek Visitors Center for park maps and information on weather and road conditions. Before heading out on a hike or a dirt-track drive, talk to a ranger about where you’re going and when you’ll be back.

Travels in Geology: Hiking Mount Nyiragongo in Virunga National Park, Congo

Mon, 04 Jun 2018 16:28:08 -0400

The Democratic Republic of Congo is not widely known for its geological wonders or natural beauty. Civil war has dominated headlines about the sprawling central African country for decades. Now, after several years of relative peace, visitors are finally trickling in to explore Congo’s untarnished wilderness. Chief among the attractions is Virunga National Park, a UNESCO World Heritage site. In Virunga, active volcanoes and mountainous ice fields loom over savannas, swamps and forests.

Getting There and Getting Around Africa

Mon, 04 Jun 2018 16:06:26 -0400

Virunga National Park may be more easily accessed from neighboring Rwanda. It is quite difficult to travel around the Democratic Republic of Congo (DRC), and there are fewer reliable flights into Congo than into Rwanda, where carriers from all over the world fly into Kigali, the capital, every day. Rwanda is beautiful, safe and accessible, making it easy and worthwhile to combine with a trip to Virunga.

Visiting Virunga's gorillas

Mon, 04 Jun 2018 16:01:38 -0400

Above: The author and others help a fellow hiker attacked by fire ants. Hikers wear masks to prevent the transmission of outside infection to the gorillas. Below: The world's last remaining mountain gorillas live in Congo's Virunga, Rwanda's Volcanoes National Park, and Uganda's Bwindi Impenetrable Forest, at an altitude of 2,195 to 4,300 meters. Credit: Bottom: Frances Lewis; top: Tom Bradley, www.tom-bradley.com

Every day, Virunga rangers bring up to eight visitors to see one of six semi-habituated gorilla families. Hikers stumble through dense jungle along a narrow path forged with machetes, warding off excruciating fire ant attacks and trying to avoid stinging nettle. My traveling companion Frances can attest to the horror of the fire ants. When we visited the gorillas after hiking the volcano, she stepped on an ant mound. It took three of us 20 minutes to pick off all the ants, some an inch long with pincers up to a third the length of their bodies. Some East African communities, including the Maasai in Kenya and Tanzania, use them as natural sutures.

Travels in Geology: Utah: Exploring the scenic byways and slot canyons of Grand Staircase-Escalante National Monument

Fri, 01 Jun 2018 17:06:25 -0400

Above: The elevated Kaiparowits Plateau extends more than 80 kilometers from the town of Escalante, Utah, to the Arizona border. Below: A self-guided trail leads upstream on the Escalante River to Escalante Natural Bridge. Credit: ©Laurie J. Schmidt

It’s no secret that the American Southwest harbors some of the most dramatic geology in the world. Although many visitors stick to the Grand Canyon, Bryce Canyon and Zion National Parks, geology-savvy travelers will also want to head to an often-overlooked region with relatively easy access to unique rock formations, fossils and cultural artifacts: the Grand Staircase-Escalante National Monument.

Getting There and Getting Around southern Utah

Fri, 01 Jun 2018 16:52:34 -0400

To get to Grand Staircase-Escalante National Monument, fly into either Salt Lake City, Utah, or Las Vegas, Nev. By vehicle, the monument can be accessed from three directions: south from Torrey, Utah, or east from Bryce Canyon, both via Scenic Byway 12, or north from Arizona via the unpaved Cottonwood Canyon Road. Southern Utah is home to half a dozen other national parks and monuments, so you’ll probably want to combine your trip with visits to some of these. Allow at least three to four days to take in all of the features mentioned in this article.

Travels in Geology: Abode of the clouds: A journey to Meghalaya, India

Fri, 01 Jun 2018 16:25:09 -0400

The high Meghalaya Plateau in northeastern India was named for the mist that often blankets its hills and forests. Meghalaya means Abode of the Clouds. Credit: Jordan Clary

While most of India swelters through the hot monsoon season, which runs from approximately June through September, the picturesque town of Shillong, on the Meghalaya Plateau in northeastern India, offers a welcome respite from the heat. Meghalaya, which translates to Abode of the Clouds, was aptly named for the mist that often hovers over the region, and the climate is salubrious, with the warmest months averaging 20 to 22 degrees Celsius. For the geo-traveler, Meghalaya offers abundant opportunities to explore some of the oldest geological formations on the planet and a glimpse of a unique area of southern Asia that travelers to India often overlook.

Getting There and Getting Around India

Fri, 01 Jun 2018 16:12:23 -0400

Most of the roads in Shillong were built during the period of British colonial rule. Credit: Jordan Clary

Shillong is connected to the rest of India by regular flights from Kolkata (Calcutta) that fly into Gopinath Bordoloi Airport in Guwahati, roughly 100 kilometers from Shillong. There is also a small airport at Umroi about 40 kilometers from Shillong with flights from Kolkata on certain days of the week. The nearest railway station is in Guwahati, which is well connected to all the major cities of India. Travel by bus is also an option.

Travels in Geology: Havasu Canyon: Land of blue-green water

Wed, 30 May 2018 17:21:16 -0400

The most famous of Havasu Canyon's waterfalls, Havasu Falls, is shown prior to the 2008 flash flood that eradicated its famous twin jets. Credit: Lon Abbott and Terri Cook

For Northern Arizona’s Havasupai tribe, whose name means “People of the Blue-Green Water,” a deep connection with the land has been the culture’s cornerstone for hundreds of years. It is easy to see why when you journey to their magnificent homeland below the Grand Canyon’s rim. There you are treated to all the majestic grandeur you expect in the Grand Canyon, plus a robust stream with the most vibrantly turquoise water this side of the tropics. The stream — Havasu Creek — rushes from one deep emerald pool to the next over a series of small travertine dams and plunges over five spectacular waterfalls as it tumbles pell-mell toward the Colorado River. The shape of each waterfall is slowly modified by the addition of new travertine rock that precipitates out of the very water that tumbles over its lip. More dramatic resculpting is done by the frequent flash floods that roar down Havasu Creek, most recently in 2008.

The River Runners' Route

Wed, 30 May 2018 17:12:32 -0400

Havasu’s magnificent waterfalls are also accessible to Grand Canyon river runners, and a stop to experience Havasu Creek’s magical turquoise water is almost mandatory on any Colorado River rafting trip.

It is typical to find 10 to 20 rafts anchored in the eddy at the creek’s mouth while rafters-turned-hikers pick their way up ledges of Cambrian-aged Muav Limestone to explore the magical stream above. Although only the most intrepid rafting parties tackle the entire 10-kilometer trail from the mouth of the creek to Mooney Falls, many stop off at intermediate points for shorter hikes. This gorgeous route includes a few short scrambles up and down cliffs where fixed ropes aid your progress. The first three-quarters of a kilometer offers straightforward hiking and wonderful scenery. More energetic hikers who wish to escape the crowds often choose to hike 6.5 kilometers from the Colorado River to Beaver Falls. More a cascade than a falls, Beaver’s beauty and its deep swimming hole both contribute prominently to its allure.

Getting There And Getting Around Arizona

Wed, 30 May 2018 17:10:13 -0400

Credit: USGS/AGI, Nicole Schmidgall & Brenna Tobler

The natural beauty of Havasu Canyon is well worth the effort it takes to get there. A limited number of people may visit at one time, so reservations are required and openings are often fully booked months in advance, especially during the Spring Break season.

Travels in Geology: Adventuring in upstate New York and remembering a life cut short

Wed, 30 May 2018 16:32:37 -0400

Of the roughly 900 waterfalls in central New York and the Finger Lakes region, one of the most impressive is 65-meter-high Taughannock Falls in Taughannock Falls State Park. Credit: ©iStockphoto.com/Michael Shake

Adam and I splashed through the water to avoid the pricker bushes along the banks of the East Branch Mohawk River. The water was frigid — it was late in the fall. We were hiking about a kilometer from Adam’s family’s cabin in New York’s Finger Lakes region, in search of a cascade spilling from the surrounding hills. Adam promised that the waterfall was just around the next bend, as he’d done already five times that morning. “Wait up!” I yelled as I bent over to pick a rock out of the water. “I found another fossil!”

Getting There and Getting Around New York

Wed, 30 May 2018 16:16:07 -0400

The Finger Lakes region has many vineyards and wineries, including these along the Seneca Lake Wine Trail. Credit: ©iStockphoto.com/Jitalia17

The Adirondack and Finger Lakes region is roughly equidistant from New York City, Montreal and Boston. By far the most scenic way to get there from New York City is by train. The northbound Amtrak from New York City follows the Hudson River at least until Albany. From there, some routes continue toward Montreal and others veer westward toward Rochester. If you snag a window seat on the left side of the train, you can spot waterfalls and birds of prey through your window. There are daily trains between New York and Montreal; trains from Boston, however, require a nonsensical transfer in New York.

Travels in Geology: Slickrock sojourn in Moab, Utah

Thu, 24 May 2018 17:07:46 -0400

Credit: Mary Caperton Morton

Remember the scene in the beginning of “Mission Impossible 2” where Tom Cruise dangles from a cliff face high above a red rock canyon, hanging on by one hand? That’s Moab. Remember the cliff that Thelma and Louise drove off at the end of their on-screen adventure? That’s Moab. Remember the slot canyon in which James Franco got stuck in “127 Hours”? That’s Moab — or nearby anyway.

Road biking in Moab

Thu, 24 May 2018 16:55:11 -0400

Credit: Mary Caperton Morton

Moab, Utah, is often called a mecca for mountain bikers. What fewer people know is that Moab is also home to some of the most spectacular road biking in the world.

Getting There and Getting Around Utah

Thu, 24 May 2018 16:53:10 -0400

Moab's famous rock shop.Credit: Mary Caperton Morton

Moab is well worth the effort required to get there. Direct daily flights to Moab’s tiny Canyonlands Field airport are offered through Great Lakes Airlines. Because a car is necessary to tour the area, a less expensive, though more time-consuming, option is to fly into one of the larger regional airports — Salt Lake City (a four-hour drive), Denver (six hours), or Grand Junction, Colo. (1.5 hours) — rent a car, and then enjoy the scenic drive to Moab.

Travels in Geology: The ephemeral Florida Keys

Thu, 24 May 2018 16:31:51 -0400

Bahia Honda Key in Florida. Credit: ©Shutterstock.com/fotomak

The Florida Keys are one of the most ephemeral places on Earth. The majority of the planet’s landmasses are millions of years old, but these islands have only been around for a few thousand years. Already, rising sea levels are threatening to submerge the young archipelago, possibly within the next century.

Getting There and Getting Around Florida

Thu, 24 May 2018 16:21:13 -0400

Credit: ©DanielSchwen, Creative Commons Attribution-ShareAlike 3.0 Unported.

The Florida Keys are a popular year-round vacation destination. There are only two seasons: the dry season, from November through May, and the wet season, from June through October.

Travels in Geology: The Canary Islands: Touring the "Hawaii of Europe"

Thu, 24 May 2018 15:45:21 -0400

Credit: ©Shutterstock.com/Roman Sigaev

I was standing on top of the world. No matter which direction I looked, steep cinder slopes dropped away sharply, merging with the thick white billows of sea fog below. A chilly wind swirled around me. In the distance, the dark peaks of other great mountains poked above the clouds, and I glimpsed shining patches of deep blue sea.

Mass wasting

Thu, 24 May 2018 15:26:20 -0400

Credit: ©Shutterstock.com/Anibal Trejo

Like all volcanic islands, Tenerife represents a balance between constructional and erosional forces. Over millions of years, repeated eruptions of magma pile up, slowly building the shield volcanoes. Occasionally, however, this long-term construction is punctuated by destruction in the form of massive, lightning-fast landslides.

Getting There and Getting Around Spain

Thu, 24 May 2018 15:24:22 -0400

Credit: ©Shutterstock.com/ArenaPhotoUK

Two airports serve Tenerife, which is a 2.5-hour plane ride away from Spain’s capital, Madrid. Most inter-island flights, plus those from mainland Spain, arrive at Tenerife Norte (Los Rodeos), 11 kilometers from Santa Cruz, the island’s largest city. Nearly all international flights (even those on Ryanair) arrive at the larger Tenerife Sur airport (Reina Sofía), located about 60 kilometers south of Santa Cruz. Although there are established bus routes across the island, the most convenient way to explore it is by car. A number of local and international agencies have depots at both airports.

Travels in Geology: Exotic dunes and atomic bombs in New Mexico's White Sands

Thu, 24 May 2018 15:03:58 -0400

Saltation of sand grains blown by wind creates a ripple pattern on the surface of the dunes. Credit: Mary Caperton Morton

The Desert Southwest is famous for out-of-this-world landscapes — some places look like the moon, others like Mars — but New Mexico’s White Sands National Monument, at the very northern end of the Chihuahuan Desert, offers an otherworldly backdrop like no other.

Missile testing

Thu, 24 May 2018 14:52:26 -0400

White Sands National Monument is surrounded by military installations, with the White Sands Missile Range to the north and Holloman Air Force Base to the east. Occasionally, the national monument and U.S. Highway 70 between Alamogordo and Las Cruces are closed due to missile testing.

Getting There and Getting Around New Mexico

Thu, 24 May 2018 14:50:10 -0400

White Sands National Monument is located in south-central New Mexico. To get there, fly into Albuquerque or El Paso, rent a car and drive 360 kilometers south on Interstate 25 from Albuquerque or 160 kilometers north from El Paso. The closest town to White Sands is Las Cruces, which has plenty of hotels, restaurants and attractions, including a natural history museum and a historic Spanish village.

Writing on the Rocks

Thu, 24 May 2018 14:48:16 -0400

Visitors to White Sands should plan on making a slight detour to the Three Rivers Petroglyph Site, an hour’s drive from the national monument. This scenic basalt ridge between White Sands and the White Mountains contains one of the greatest concentrations of petroglyphs anywhere in the Southwest. More than 21,000 petroglyphs of geometric and abstract shapes, faces and animals were etched into the dark rocks by the Jornada Mogollon people, who lived in this area between A.D. 1000 and 1400.

Travels in Geology: Western Nebraska's geoheritage gems

Thu, 24 May 2018 13:47:40 -0400

Western Nebraska's rock monuments, rising above the Great Plains, have significant historical, cultural and scientific value. Credit: Kahvc7s

Western Nebraska does not usually appear on lists of travel destinations, yet this region has a historical and cultural significance as vast as its landscape. For more than 500,000 westbound pioneers who tenaciously crossed the continent along the Oregon, California and Mormon trails, this region — where the flat plains give way to a rugged terrain of sculpted badlands and rocky bluffs — heralded their arrival in the West.

Getting There and Getting Around Nebraska

Thu, 24 May 2018 13:33:46 -0400

Carhenge was recently named America's second-wackiest attraction by TripAdvisor. Carhenge was recently named America's second-wackiest attraction by TripAdvisor. Credit: ©Shutterstock.com/Chad Bontrager; top: ©Jimmy S. Emerson, DVM

Many visitors to western Nebraska’s geoheritage sites will probably be “driving through” en route to more famous sites, such as Yellowstone, Grand Teton and Rocky Mountain national parks to the west or the Badlands and Mount Rushmore just to the north. But commercial air service is available directly into Scottsbluff, Neb., as well as Cheyenne, Wyo., and Denver, Colo. (about 160 and 320 kilometers away, respectively). A car is necessary to get around the area; you can rent one at any of these airports if you choose to fly in. If you’re driving through the area on Interstate 80, which runs from New York to San Francisco, you’ll pass through the Nebraskan panhandle.

Travels in Geology: The wild east of Wyoming: Bone wars, outlaw hideouts and crack climbing

Thu, 24 May 2018 13:07:00 -0400

Eastern Wyoming is known for its wide open spaces. Credit: Mary Caperton Morton

When vacationers plan trips to Wyoming, the western half of the state, with its grizzly bears, Grand Tetons and Yellowstone National Park, tends to be the biggest draw. But Eastern Wyoming — home to bone wars, outlaw hideouts and the nation’s first national monument — also boasts a captivating mix of Wild West history and geologic marvels.

Boondocking 101: How to camp for free in Wyoming

Thu, 24 May 2018 12:51:26 -0400

Credit: Mary Caperton Morton

When I drove this loop around Wyoming last spring, I did it in 10 days, camped out every night and didn’t pay for a single campsite. Wyoming is replete with public land: Nearly half of the state’s lands are held by the federal government and managed by the Bureau of Land Management and the U.S. Forest Service. Travelers are free to camp on BLM lands or national grasslands or in national forests, a practice known as dispersed camping, boondocking or coyote camping. You can stay in one site up to 14 days, but you must honor “Leave No Trace” ethics: After you leave your campsite, there should be no trace that you were ever there.

Getting There and Getting Around Wyoming

Thu, 24 May 2018 12:48:23 -0400

"Road" is a loose term in parts of Wyoming. But even on a lot of main roads, you can go a long way without seeing a sign of civilization. Credit: Mary Caperton Morton

To drive all or part of this loop, fly into Cheyenne and rent a car. You can also fly into Denver, 160 kilometers south of Cheyenne. The loop runs from Cheyenne to Laramie, then up through Casper, Buffalo, Gillette and Devils Tower before returning back south to Cheyenne via U.S. Highway 85. Primitive and developed camping opportunities abound in Wyoming, and hotels, motels and other accommodations can be found in the cities along the loop.

Travels in Geology: The Bay of Kotor: Europe's southernmost "Fjord"

Thu, 24 May 2018 12:26:04 -0400

The Bay of Kotor formed when rising sea levels drowned an ancient river valley — a geographic feature called a ria. Credit: Background: ©Shutterstock.com/Gerardo Borbolla; left: Terri Cook and Lon Abbott

With its stunning backdrop of steep, imposing cliffs that plummet to a narrow inlet of the sparkling Adriatic Sea, Montenegro’s Bay of Kotor is often called Europe’s southernmost fjord. But this is a mistake. Unlike the finger-like inlets adorning the coasts of more famous European destinations like Norway and Iceland, the Bay of Kotor was not carved by glaciers. This impressive bay was instead created when rising sea levels drowned an ancient river valley — a feature geomorphologists call a ria.

Getting There and Getting Around Croatia

Thu, 24 May 2018 12:05:01 -0400

Most visitors to the Bay of Kotor arrive via cruise ship or an all-day excursion from Dubrovnik, Croatia. These options usually leave only a few hours to enjoy Kotor and neglect most of the bay’s other attractions.

Travels in Geology: A taste of Provence

Thu, 24 May 2018 11:29:00 -0400

Provence, a region in southern France, is picturesquely nestled between the soaring Alps, the shining Mediterranean Sea, and the historic Rhône River. Credit: top: ©Shutterstock.com/Gordon Bell; bottom: Kathleen Cantner, AGI; globe: AGI/NASA

Nestled among the soaring Alps, the shining Mediterranean Sea, and the historic Rhône River, Provence, France — one of the world’s foremost tourist destinations — offers visitors scenic, gourmet, and geologic delights. The region’s rugged mountains, extensive plateaus and vineyard-lined slopes result from the Alpine orogeny, the mountain-building episode that uplifted the Pyrenees and the Alps in southwestern and southeastern France. The land in between was more modestly deformed, then gradually eroded over millions of years, to create the chefs-d’oeuvre — the masterpiece — that we now call Provence.

Southern Rhone wines

Thu, 24 May 2018 11:13:49 -0400

The Rhône Valley’s wine-growing regions are divided into two sections, with only its southern portion located in Provence. The Southern Rhône is best known for distinctively spicy red wines, the result of producing extremely low yields from very old vines whose grapes’ sugar content and acidity levels are further concentrated by the region’s fierce winds. The result is unusually dense wines full of earthy flavors.

Getting There and Getting Around France

Thu, 24 May 2018 11:09:03 -0400

Most flights to France from the U.S. land in Paris. If you are heading directly to Provence, you can fly from Paris to Marseille-Provence Airport. Another option is France’s high-speed TGV train, which zips between the capital and Marseille, Aix-en-Provence, Avignon, and Arles. During the summer, Eurostar trains run directly from London to Avignon, and there are also direct flights from London to Marseille. In addition, ferries sail regularly to Marseille from Sardinia, Corsica, and Tunisia. Although the public transportation system is excellent in France’s urban areas, the most convenient way to explore Provence’s countryside is by car. Most visitors arrive with accommodations already booked, a wise strategy especially during the bustling summer months. Websites such as booking.com offer a wide range of properties throughout Provence. If you are planning on staying at least a week in one location, consider renting a gîte — a small, furnished holiday home typically located in a rural area — through the website http://en.gites-de-france.com. Be aware that you often need to wire a deposit ahead of time to the owner, who may not speak much English. Provence isn’t cheap. Camping is a great way to save money, see some out-of-the-way places, and meet locals and other (usually European) tourists. If you don’t wish to haul camping gear with you, renting a camper van is another option. If you decide to hike on Mont Ventoux, good places to begin are the villages of les Fébriers or les Colombets near Bédoin, or from Chalet Liotard, located on the northwest side much closer to the summit. If you choose to cycle up the giant, the town of Malaucène has several shops, including Ventoux Bikes, where you can rent a reliable bike, as well as some great cafes to catch up on some post-ride calories.

Down to Earth With: John 'Jack' Reed Jr.

Wed, 23 May 2018 17:27:42 -0400

John "Jack" Reed Jr. Credit: Mountaineers Books

Geologist Jack Reed spent his career studying rocks the most strenuous way someone can — by climbing them. During much of his 47 years with the U.S. Geological Survey, Reed clung to rock faces in Alaska, Wyoming and Colorado, while creating geologic maps of North America’s tallest mountain ranges. Along the way, he published dozens of books for climbers and hikers on the geology of places like the Tetons in Wyoming, Seneca Rocks in West Virginia, Shenandoah National Park in Virginia and, most recently, “Rocks Above the Clouds: A Climber’s Guide to Colorado Mountain Geology.” Shortly before his latest book hit the shelves, Reed took some time out of his busy retirement schedule to speak with EARTH contributor and fellow climber Mary Caperton Morton.

Down to Earth With: Maurice J. 'Ric' Terman

Wed, 23 May 2018 17:22:13 -0400

Maurice Terman. Credit: Courtesy of Maurice Terman

A general wants to advance his army of tanks, but doesn’t know if the terrain he plans to cross will allow it. Tanks can’t go up steep slopes, for instance. And they can’t knock down large trees or traverse soft ground like peat bogs. That’s where military geologists come in — earth scientists who scope out the terrain to determine its suitability for different types of movement and construction.

Down to Earth With: New congressional science fellows

Wed, 23 May 2018 17:09:52 -0400

Last month, a new Congress and president came to Washington, D.C. And with them came new staff, including five geoscience congressional science fellows. The fellows will take their scientific prowess to the Hill, and will use their training to work with senators, representatives and committees on policy issues. But the transition from field boot to suit jacket won’t be easy, they told EARTH reporter Brian Fisher Johnson.

Down to Earth With: Randy Olson

Wed, 23 May 2018 16:19:22 -0400

Randy Olson poses with a flock of dodos at the 2006 Tribeca Film Festival. Credit: Katarzyna Balug

Marine biologist-turned-filmmaker Randy Olson made a name for himself in 2006 with the release of his first feature-length movie, “Flock of the Dodos: The Evolution-Intelligent Design Circus.” He followed that success with last year’s “Sizzle: A Global Warming Comedy.” These movies feature hot-button science issues, but they are not documentaries. Rather, Olson says, they are designed to entertain and spark an interest in the scientific topic — whether evolution or climate change — so that viewers will want to learn more.

Down to Earth With: Ted Irving

Wed, 23 May 2018 15:44:57 -0400

Ted Irving. Credit: Courtesy of Ted Irving

Geoscience students today may take plate tectonics for granted, but the concept that Earth has a mobile crust has only been generally accepted for the past 40 years. This modern concept is due in part to the work of Ted Irving, a geologist and scientist emeritus with the Geological Survey of Canada. In the 1950s, Irving was one of the first scientists to perform a physical test of — and find hard evidence for — Alfred Wegener’s 1912 hypothesis of continental drift. Continental drift was a precursor to plate tectonics theory, which describes how Earth’s surface is not a single shell, but is divided into large plates that are constantly moving past each other.

Down to Earth With: Peter Brewer

Wed, 23 May 2018 15:21:29 -0400

Whether through deep-sea gas hydrate experiments, lasers or asphyxiating squid, Peter Brewer is always seeking new ways to understand the changing chemistry of the oceans. Brewer has embarked on a series of groundbreaking projects throughout his career. During his nearly 24 years at the Woods Hole Oceanographic Institution, he was the chief architect of the Joint Global Ocean Flux Study, launched by the United States in the late 1980s to track the cycling of carbon and other chemical elements between the atmosphere, oceans and seafloor — and to understand human impacts on these cycles.

Down to Earth With: Jessica Whiteside

Wed, 23 May 2018 14:59:19 -0400

Jessica Whiteside (middle) is an assistant geology professor at Brown University. Credit: Courtesy of Jessica Whiteside

From Morocco to Connecticut, Jessica Whiteside has explored almost every Mesozoic rock outcrop there is. And she’s only three years out of graduate school. With a bachelor’s degree from Mount Holyoke College in South Hadley, Mass., and two master’s degrees and a doctorate from Columbia University in New York, N.Y., under her belt, Whitehouse is now in Providence, R.I., working as an assistant professor of geological sciences at Brown University.

Down to Earth With: Matt Kondolf

Wed, 23 May 2018 12:07:51 -0400

Matt Kondolf. Credit: Courtesy of Matt Kondolf

As a fluvial geomorphologist teaching in the Landscape Architecture and Environmental Planning Department at the University of California at Berkeley, Matt Kondolf is an ambassador from the earth sciences to landscape designers and environmental planners. Kondolf’s research in river management ranges from the impacts of urbanization on runoff and sediment yield, to river restoration, to managing salmon populations and fishing. In classes like “Hydrology for Planners” and “Ecological Analysis in Urban Design,” he encourages up-and-coming environmental planners and designers to think carefully about the geologic processes that control river formation, as well as the roles that rivers play within ecosystems. He is also active in the policy discussions that are shaping California’s and the nation’s approaches to river management.

Down to Earth With: Mike Gallagher

Wed, 23 May 2018 11:31:14 -0400

Mike Gallagher. Credit: Germaine Price

Mike Gallagher is not your typical science educator. After spending three years as a researcher and field geologist with the U.S. Geological Survey in Menlo Park, Calif., Gallagher decided to become a teacher after budget cuts at USGS in the late 1980s encouraged him to reconsider his career track. Gallagher went on to earn a Washington state teaching certificate (while renting a place in the belfry of a local church). As a teacher in Washington, Gallagher engaged his students with hands-on science research projects: By 1999, two of his students had even presented their research on the water quality of a local stream to then-Governor Gary Locke, who is now secretary of commerce. A windsurfer in his spare time, Gallagher now works for Michigan’s Oakland Intermediate School District, advising districts and teachers on how to improve their science education programs.

Down to Earth With: Sharon Mosher

Wed, 23 May 2018 10:56:04 -0400

Sharon Mosher. Credit: Jackson School of Geosciences, University of Texas at Austin

Sharon Mosher was born with a rock in her hand, as her mom used to say. As a child in Illinois, she was fascinated by geology, conducting mineral tests on rocks in the chemistry lab her dad set up for her in their basement. She decided she wanted to be a geologist the moment she learned that’s what you call a person who studies rocks.

Down to Earth With: Todd Hoefen

Tue, 22 May 2018 17:02:40 -0400

Todd Hoefen collects ash samples from the Station Fire in Southern California in 2009. Credit: Courtesy of Todd Hoefen

On any given day, you might find Todd Hoefen studying the material properties of other planets, building remote sensing applications, sampling dust from the rubble of natural and human-made disasters, or playing drums with the members of his former rock band, Oakhurst.

Down to Earth With: Katerina Dontsova

Tue, 22 May 2018 16:41:31 -0400

Soil scientist Katerina Dontsova didn’t imagine she would be working at one of the nation’s most famous laboratories when she arrived at Purdue University in West Lafayette, Ind., from the Ukraine as an undergraduate exchange student in 1993. But after earning a doctorate in soil chemistry from Purdue and working as a contractor for the U.S. Army Corps of Engineers in Mississippi, Dontsova did just that, landing a job at Biosphere 2, outside Tucson, Ariz., in 2008.

Down to Earth With: Nick Brooks

Tue, 22 May 2018 16:17:08 -0400

Nick Brooks surveys the landscape at Rekeiz Lemgassem, Western Sahara. Credit: Nick Brooks

More than 6,000 years ago, the world’s most famous desert was no desert at all. A wet, grassy landscape, the Sahara supported populations of hunter-gatherers. But between 5,000 and 6,000 years ago, the Sahara started to dry out. The rapid climate change forced the Sahara’s human inhabitants to adapt — some people became more sedentary and settled near oases while others took up cattle herding and traveled between the desert’s dwindling resources. Once the desert became too inhospitable to support even a pastoralist’s lifestyle, people migrated southward.

Down to Earth With: Jeffrey Post

Tue, 22 May 2018 15:41:08 -0400

Jeffrey Post has been the curator of the Smithsonian's National Gem and Mineral Collection for more than two decades. Credit: Smithsonian Institution

The gems and minerals exhibit at the Smithsonian Institution’s National Museum of Natural History in Washington, D.C., has more than 3,000 pieces; the entire collection has more than 360,000 pieces. From slabs of granite to the ultimate gem, the Hope Diamond, the collection is one of the finest displays of geology in the world. And one person, Jeffrey Post, oversees the entire collection. As the curator of the National Gem and Mineral Collection for the past 20 years, Post has helped obtain some of the collection’s most stunning pieces as well as pursued research behind the scenes. Post sat down with Meg Marquardt, an intern at EARTH, to talk about his path to the Smithsonian, the charm of the collection and his research into environmentally important minerals.

Down to Earth With: Dr. Jonathan Patz

Tue, 22 May 2018 15:23:10 -0400

Dr. Jonathan Patz. Credit: Courtesy of University of Wisconsin

From stitching up cuts in Missoula, Mont., to authoring parts of the Intergovernmental Panel on Climate Change reports, Dr. Jonathan Patz has made helping people stay healthy his life’s work. With a joint appointment at the University of Wisconsin at Madison’s School of Medicine and its Nelson Institute for Environmental Studies, Patz is in a unique position to explore global climate change as a matter of public health.

Down to Earth With: Matthew Parker

Tue, 22 May 2018 15:08:44 -0400

Matthew Parker out in the field with the VORTEX2 project near Dalton, Neb. Credit: George Bryan

Matthew Parker In 1985, the television show NOVA dedicated an entire hour to the pioneers of tornado research, the men and women who first spent their summers crisscrossing the central United States in pursuit of data on the perfect tornado. Long before the blockbuster movie “Twister” sparked an entire legion of amateur storm chasers looking for a thrill, that NOVA documentary gave rise to Matthew Parker’s lifelong drive to understand the science behind one of Mother Nature’s deadliest weapons. Now an atmospheric scientist, Parker heads the convective storm research group at North Carolina State University in Raleigh. Among other projects, Parker is involved with VORTEX2 (Verification of the Origins of Rotation in Tornadoes Experiment 2), a descendant of the TOTO (Totable Tornado Observatory) system used in the NOVA documentary. As VORTEX2 closes out its last season of gathering data, Parker spoke with Meg Marquardt, an intern at EARTH magazine, about what sparked his interested in severe weather and how far tornado observation has come since those early days.

Down to Earth With: Hope Jahren

Tue, 22 May 2018 11:43:43 -0400

Courtesy of Hope Jahren

Hope Jahren is often described as a biogeologist, but that seems too narrow a description. Currently a professor at the University of Hawaii in Manoa, Jahren has studied everything from fossils and french fries to paleoclimate and plants. After graduating from the University of Minnesota in Minneapolis in 1991 with a degree in geology, Jahren studied stream chemistry in Norway as a Fulbright scholar. She completed a doctorate in soil science at the University of California at Berkeley in 1996 and taught at Johns Hopkins University in Baltimore, Md., before moving to Hawaii in 2008. Jahren talked with freelance writer Sam Lemonick about her diverse interests and her return this year to Norway, where she has another Fulbright grant, this time to study how climate affects the growth patterns of plants.

When more humidity means less water

Wed, 16 May 2018 11:31:39 -0400

Snow cover across much of the U.S. West can be seen in this photo, taken from the International Space Station on March 3. Credit: ISS Crew Earth Observations Facility and the Earth Science and Remote Sensing Unit, Johnson Space Center, NASA

Scientists have long assumed that temperature is the main control on melting of winter snowpacks across the mountainous western United States. In a recent study, however, scientists suggest that regional humidity may have a larger impact than temperature.

El Nino "flavors" affect California rainfall

Fri, 11 May 2018 15:56:06 -0400

In October 2015, NOAA's precipitation outlook for the winter of 2015 - 2016 suggested the odds were good for a wetter-than-average winter across Southern California. Credit: NOAA Climate Prediction Center

Twenty years ago, the 1997–98 El Niño surpassed the 1982–83 event to become the strongest El Niño ever recorded, contributing to famine and drought in Southeast Asia, devastating floods in Southern California, and other natural disasters. By many metrics, the 2015–16 El Niño bested both to claim the title of the strongest El Niño on record. This most recent event, nicknamed the “Godzilla El Niño,” did contribute to extreme weather in parts of the world, including disastrous fires in Indonesia and the longest, global coral-bleaching event on record. However, it did not have the anticipated effect on California, which, at the time, was in the midst of a severe multi-year drought. In a recent study, researchers suggest the 2015–16 El Niño was the wrong “flavor” to bring heavy precipitation to the state.

Geologic evidence confirms existence of 405,000-year Milankovitch cycle

Fri, 11 May 2018 09:04:35 -0400

Rock samples cored from the Triassic Chinle Formation in Petrified Forest National Park in Arizona were dated and correlated to Triassic rocks from the Newark Basin to determine the ages and timing of climate cycles recorded in the rocks. The new research confirms the existence of a predicted 405,000-year Milankovitch cycle governed by Jupiter and Venus. Credit: Kevin Krajick/Lamont-Doherty Earth Observatory

Earth’s rock record preserves evidence of numerous natural processes, from evolution and extinction to catastrophes and climate change, and sometimes even planetary configurations.

Geoscience on Film: The Burma Arc in Myanmar

Wed, 02 May 2018 11:03:44 -0400

Some 10,000 temples and pagodas — built in the 11th, 12th and 13th centuries — used to stand in what's now the Bagan Archaeological Zone along the Irawaddy River in Myanmar. About 2,200 of the structures remain today. Credit: Doug Prose

Doug Prose, formerly a geologist with the U.S. Geological Survey, has co-produced documentaries showcasing Earth and the geosciences with his partner and wife, Diane LaMacchia, through their nonprofit Earth Images Foundation since 1992. Recent films include “Earth: The Inside Story” and “Italy’s Mystery Mountains,” both released in 2014. Their latest documentary, “The Himalaya Connection,” began airing on PBS stations in April. Prose has previously written and blogged for EARTH about the pair’s experience shooting and preparing “Connection,” which involved six separate trips to Bangladesh, Bhutan, India, Mongolia and Nepal from 2011 to 2016. They recently traveled back to the region for their next project. Prose wrote about the trip while there, and filed the following series of posts upon returning home. Read posts in this series, as well as from prior trips, here.

Skate eggs found on hydrothermal vents

Tue, 01 May 2018 16:25:23 -0400

A skate egg case found near hydrothermal vents in the Galápagos spreading center. Credit: Ocean Exploration Trust.

In July 2016, a team of scientists came upon a surprise 1,660 meters beneath the ocean’s surface near the Galápagos Islands: a clutch of yellow eggs, laid by a Pacific white skate, a cousin of rays and sharks. It was not the eggs themselves that surprised the team, but where they were found: near a volcanic hydrothermal vent. The large number of eggs at the site led the team to suggest that the skate was likely using the vent’s heat to incubate the eggs.

Are diatoms triggering submarine landslides?

Tue, 01 May 2018 16:19:16 -0400

A scanning electron microscope image of marine diatom mud. Credit: Gauvain Wiemer/MARUM/University of Bremen.

Far beneath the ocean’s surface, puzzling deposits from huge submarine landslides can be found amid expanses of nearly flat ocean floor. Without steep terrain, what causes these megaslides? In a new study, scientists who delved into deep-sea drilling records report a potential trigger for one such slide off the coast of northwest Africa: diatom ooze.

Which warm waters boosted Hurricane Harvey?

Tue, 01 May 2018 16:05:05 -0400

Harvey rapidly intensified from a tropical storm to a Category 4 hurricane as it moved across the Gulf of Mexico. Warmer colors indicate higher ocean temperatures in the Gulf, and higher wind speeds on the storm track. Credit: K. Cantner, AGI , with data from UODL and Potter et al.

Last August, Hurricane Harvey walloped Texas, dropping more than 100 centimeters of rain on Houston and nearby areas, and causing more than $125 billion in damage. But almost nobody saw it coming. In the days before Harvey made landfall 60 kilometers east of Corpus Christi, the tropical storm barely registered as a threat, but within 30 hours it escalated from a tropical storm into a Category 4 hurricane. Using data collected before and during the storm, scientists are piecing together how Harvey became so ferocious so fast, an effort that could help scientists better predict which future storms might have similarly rapid intensifications.

From silver to snow: Full cloud seeding cycle observed

Tue, 01 May 2018 15:58:44 -0400

A "Doppler on Wheels" truck, equipped with X-band radar, atop Packer John Mountain in the Salmon River Range in central Idaho tracks the formation of ice particles during cloud seeding experiments. Credit: Josh Aikens.

Cloud seeding — adding particles to clouds to modify precipitation patterns — has been suggested as a way to trigger rain and snowfall, which could help sustain mountain snowpack and water supplies across the western U.S. However, it has been challenging to demonstrate the technique’s effectiveness and efficiency, in part because direct observations of the full chain of events involved in cloud seeding have been lacking.

Lava shaped Lake Tahoe

Tue, 01 May 2018 15:50:58 -0400

The headwaters of the Truckee River begin at the Lake Tahoe dam. Credit: Dinuraj K, CC BY 2.0.

With its preternaturally clear blue waters, Lake Tahoe is tranquil today, but the deep lake straddling the border of California and Nevada was once the site of repeated lava flows. In a new study, researchers used radiometric argon dating to describe how episodes of volcanism created the landscape around the largest alpine lake in North America.

Swelling clay slows landslides

Tue, 01 May 2018 15:47:48 -0400

Researchers study the Two Towers Landslide in Northern California, which moves about a meter a year and is representative of thousands of clay-rich landslides worldwide. Credit: William Schulz.

Rainfall can trigger landslides, and it can also cause slow-moving slides to speed up. But researchers have observed that rain also appears to cause landslides composed of clay-rich material to take longer to start moving, and to move slower than expected.

Mineral Resource of the Month: Chromium

Tue, 01 May 2018 13:02:55 -0400

PRODUCTION

Chromite seams (dark layers) located in the Bushveld Complex, South Africa. Credit: courtesy Klaus Schultz, USGS.

GEOLOGIC OCCURENCE

Although chromium is a metal, it does not occur naturally in metallic form. Chromium can be found in many minerals, but the only economically significant chromium-bearing mineral is chromite. Chromite has been mined from four different deposit types: stratiform chromite, podiform chromite, placer chromite, and laterite deposits. Most of the world’s resources, however, are located in stratiform chromite deposits, such as the Bushveld Complex in South Africa. The economic potential of chromite resources depends on the thickness and continuity of the deposit and on the grade of the ore. Many of the major stratiform chromite deposits also contain economic levels of platinum, palladium, rhodium, osmium, iridium and ruthenium.

"Greening" stormwater in Philadelphia

Tue, 01 May 2018 12:04:17 -0400

When environmental geologist David Wilcots joined Sci-Tek Consultants in 2014, he became involved with the Philadelphia Water Department’s Green Stormwater Infrastructure project. Sci-Tek’s goal was to redesign certain areas of the city’s urban landscape so that “less stormwater goes into the sewage system” and more goes into the ground, explains Wilcots. Doing so not only helps prevent flooding, but also lightens the load on sewage treatment plants. He manages a team of designers, data analysts and environmental scientists who are “gathering the stormwater flow data from around the city at hundreds of locations.”

Geologic Column: Rebranding Alexander

Tue, 01 May 2018 11:54:29 -0400

Credit: Yuval Y CC BY-SA 2.0

by Ward Chesworth

“With great power comes great responsibility.” — Various (including “Amazing Fantasy #15,” the comic in which Spider-Man was first introduced)

As near as I can make out, William Bonney was a psychopath. Before Pat Garrett shot him dead in 1881, Bonney was known to have killed at least eight men (he claimed 21), all before he reached age 22. He’s known to history as Billy the Kid, and that label “Kid” softens our view of him somewhat. Kids are the delightful young of the tribe — playful and sometimes mischievous, but psychopaths? “Never,” you say, thinking of a well-loved kid of your own, perhaps. That’s why Billy’s been portrayed in movies and on TV as basically loveable but a bit mixed up.

Travels in Geology: Rafting the Salmon River through the Idaho Batholith

Tue, 01 May 2018 11:13:02 -0400

Rafting the Main Salmon River across Idaho offers a thrilling whitewater adventure, as well as a tour through several of the state's geologic provinces. Credit: Bureau of Land Management.

Give a river time and it will chart a path through even the mightiest mountains, cutting down through the rocky record of Earth’s long history. Rafting down a river, then, can give you a front-row seat to a geologic story that unfolds as you go past. Such is the case on a trip down the Main Salmon River, which courses first north and then west across northern Idaho over Precambrian metamorphic rocks, as well as granitic rocks of the Idaho Batholith, which intruded into the crust during the Cretaceous Period before being exposed at the surface. The finale of this Salmon trip — which takes about six to eight days to finish — arises as the river flows past what was once the edge of North America and over former island arcs sutured onto the continent during the Mesozoic.

Getting there and getting around Idaho

Tue, 01 May 2018 10:57:33 -0400

Most river trips down the Main Salmon begin at the boat ramp at Corn Creek Campground, where rafters rig their crafts and have their gear and permit checked by a U.S. Forest Service ranger. Credit: U.S. Department of Agriculture.

If you’re interested in a trip down the Main Salmon, you have two options: put a trip together yourself, or hire a professional outfitter to take you. Permits are required for self-organized trips between June 20 and Sept. 7. Permits are awarded through a lottery via www.recreation.gov, and the lottery application period runs from Dec. 1 to Jan. 31. Though they can be very hard to get, each permit allows a maximum of 25 people to travel the river: In 2017, there were 9,000 applications for just 310 launches. (It may be a good idea to have a lot of people from your group apply.) Permits are not required if you go with an outfitter. For outfitter suggestions, check with the U.S. Forest Service. Lastly, bring a waterproof guidebook that you can keep open as you splash through waves. I highly recommend “RiverMaps Guide to the Middle Fork and Main Salmon Rivers, Idaho," which contains the mileages referenced above.

Fieldwork among the pixels: Virtual and augmented reality diversify geoscience education

Tue, 01 May 2018 10:51:05 -0400

A photosphere view of a glacial erratic featured in a virtual reality geology field trip to Columns of the Giants in the Sierra Nevada of California. Credit: Ryan Hollister.

by Sarah Derouin

Data-driven discovery reveals Earth's missing minerals

Tue, 01 May 2018 10:31:26 -0400

Missing Minerals graphic. Credit: Image credit: K. Cantner.

Fueled by advances in computing power and analytical methods, researchers in a growing number of scientific fields have taken to mining large datasets to reveal big-picture insights. By tallying the words that appear in a sampling of a book’s pages, for example, lexicologists — interested in tracking trends over time in language or literature — can mathematically predict the total number of distinct words in the book or, say, the number of different words containing a certain letter or certain combinations of letters.

Geoscience on Film: Roadcuts and rockfalls in mountainous Mizoram

Wed, 18 Apr 2018 13:15:11 -0400

Aizawl, the capital of the Indian state of Mizoram, is draped over a mountain ridge. An example of the typical construction style in Aizawl — a multi-story home supported by concrete stilts atop the steep hillside — can be seen at right in the foreground. The remnant of a damaging landslide can be seen in the center of the photograph. Credit: Martin Prose

Geomedia: Television: "One Strange Rock" is Superlative

Wed, 11 Apr 2018 13:58:52 -0400

If I only had one word to describe the new 10-part National Geographic documentary series “One Strange Rock,” produced by Darren Aronofsky and Jane Root, it would be “superlative.” But don’t misunderstand me: The series is not remarkable because it’s the best nature documentary I’ve ever seen. It’s not, although it does feature gorgeous footage and state-of-the-art, digitally generated animations, and perhaps covers a wider range of earth science topics than other documentaries in the genre. Instead, it is superlative in the way that Americans make many things superlative — with hyperbole.

Geologic Column: A world without measure

Wed, 11 Apr 2018 09:57:40 -0400

Various hand-derived units of measurement. A span, for example, is represented by line 4. Credit: public domain

Have you ever stopped to consider how difficult our lives would be without uniform systems of measurement? Imagine going to the gas station to fill up your vehicle and trying to figure out the volume of gas you’re actually getting. Or buying produce and being unsure if you’re paying the same price per weight as other shoppers. Or having laser eye surgery to correct your vision without knowing whether the laser’s power is accurately known. Whether you use English measurements — the convention in the U.S. — or metric like most of the rest of the world, you’re using a uniform system, and it’s possible to easily translate between one system and another. But it wasn’t always like that.

Rising waters sink seafloors

Tue, 10 Apr 2018 12:14:47 -0400

Estimates of ocean-bottom deformation (a), relative sea-level change (b), and geocentric, or absolute, sea-level change (c) between 1993 and 2014 are shown here. The weight of added water has depressed the seafloor globally by an average of about 0.13 millimeters per year (mm/y) over that time, according to new research, although the seafloor across far northern latitudes has actually risen due to melting ice and the redistribution of Arctic waters to areas south. Blue lines in each panel indicate where local change equals the average global ocean trend, the values of which are shown below each panel. Credit: Frederikse et al., Geophysical Research Letters, December 2017.

Predicting how much the ocean surface will rise in the coming years requires complicated, global-scale bookkeeping of the many factors that affect sea levels. In a new study, scientists have, for the first time, quantified the role of ocean-bottom deformation — the gradual deepening of ocean basins under the weight of more water — in both global and regional sea-level rise, an effort that may help produce more accurate sea-level projections.

Ice (Re)Cap: May 2018

Tue, 10 Apr 2018 12:04:52 -0400

Researchers studying soil cores from Alaska estimate that soils in Northern Hemisphere permafrost regions contain far more mercury than all other soils around the world combined. Credit: National Park Service/C. Ciancibelli.

Radium levels suggest Arctic Ocean chemistry is changing

Tue, 10 Apr 2018 11:44:26 -0400

In 2015, researchers measured radium in the Arctic Ocean from the Chukchi Shelf (where the voyage started) to the North Pole. Elevated radium levels (shown in bright yellow along the cruise route) were found near the North Pole, possibly as a result of transport from the East Siberian Arctic Shelf. Credit: Natalie Renier, Woods Hole Oceanographic Institution.

Rising temperatures have already caused changes in the Arctic environment, like diminishing sea ice and thawing permafrost. Now, it appears that sea-ice loss could be throwing Arctic Ocean chemistry out of whack.

Battery recycling underlies elevated lead in African soils

Tue, 10 Apr 2018 11:22:11 -0400

Lead-acid batteries — used to power motor vehicles and cellphone towers, and for power storage at wind and solar farms — are one of the most recyclable products, but they are also highly toxic. Credit: baselactionnetwork, CC BY-ND 2.0.

Of all the recycling industries in the world, lead-acid battery recycling is one of the most profitable — and one of the most toxic. In the U.S., regulations on the industry have dramatically reduced lead exposure and pollution at battery recycling plants. But in Africa, where the industry is growing and largely unregulated, lead levels are skyrocketing. A new study in Environmental Research looking at environmental lead levels in seven African countries is shining a spotlight on the ongoing public health crisis.

Unprecedented exploration of undersea volcano yields surprising results

Tue, 10 Apr 2018 11:14:14 -0400

Lava from the 2012 eruption of the Havre underwater volcano is shown in shades of red in this high-resolution model. Credit: University of Tasmania/Woods Hole Oceanographic Institution.

Underwater volcanic eruptions happen every day, but because of the vastness of the ocean and the great depth of water blocking the view, catching an active eruption is a game of chance. In fact, the largest-known underwater eruption of the past century was something of a fluke discovery. In July 2012, an airline passenger spotted a huge pumice raft floating in the South Pacific during a flight to Auckland, New Zealand. Upon landing, she alerted researchers, and scientists confirmed the 400-square-kilometer pumice raft near the Havre Seamount using NASA satellite imagery.

World's longest underwater cave found in Mexico

Tue, 10 Apr 2018 11:06:37 -0400

A connection between the Dos Ojos (seen here) and Sac Actun caves near Tulum, Mexico, was recently discovered. The newly combined cave system is now the longest-known underwater cave in the world. Credit: Guillén Pérez, CC BY-ND 2.0

In January, scientists and underwater explorers working with the Great Maya Aquifer (Gran Acuífero Maya, or GAM) project discovered the world’s longest flooded cave system, which stretches 347 kilometers in Quintana Roo on Mexico’s Yucatán Peninsula.

Benchmarks: May 3, 2003: New Hampshire's Old Man of the Mountain falls

Tue, 10 Apr 2018 10:06:18 -0400

New Hampshire's famed face-shaped outcrop of Conway Granite, known as the Old Man of the Mountain, shown in April 2003. It collapsed one month later. Credit: Jeffrey Joseph, public domain.

On May 2, 2003, the Old Man of the Mountain, New Hampshire’s famous face-shaped granite formation, adorned the side of Cannon Mountain in Franconia Notch State Park, just as it had for millennia. But by the next morning, it was gone: The iconic stone face had fallen.

Travels in Geology: Northern Oman: Stunning canyons, towering dunes and the world's largest ophiolite

Mon, 09 Apr 2018 15:41:50 -0400

Wadi Nakl, the Grand Canyon of Arabia, is just one of Northern Oman's many highlights. Credit: Lon Abbott and Terri Cook.

Hot, off-the-beaten path and situated amid an oftentimes turbulent region, Oman may not top many travelers’ lists of desired destinations. But if you’re into geology, it should: The small sultanate, itself politically stable, hosts the world’s biggest and most intact ophiolite, along with stunning canyons that plunge into turquoise swimming holes, lush palm oases and Bronze Age tombs, pristine beaches where endangered sea turtles struggle back to the sea after laying their eggs, and endless fields of sand dunes where you can camp beneath the stars. You’ll come for the ophiolites, and stay for the rest.

Getting there and getting around Oman

Mon, 09 Apr 2018 15:25:15 -0400

Oman’s main gateway is Muscat International Airport (MCT), which offers service to most major Middle Eastern and European cities. There are no direct flights to Oman from North America; it’s usually most convenient to fly through Dubai, Doha, Bahrain or a major European city. Emirates, Qatar Airways, Gulf Air, Oman Air and Turkish Airlines are among those that offer connecting service. The airport is located on the western edge of the capital city; if your hotel doesn’t offer a free shuttle, you can reach the downtown via blue-striped airport taxis, which operate on a fixed, prepaid rate, or one of the microbuses that depart from the opposite side of the footbridge that spans the highway outside the airport.

Oceanic crust in all its glory

Mon, 09 Apr 2018 15:15:29 -0400

One of the world's best exposures of pillow lavas graced the cover of Geotimes, EARTH's predecessor, in 1975. Credit: American Geosciences Institute.

The classic ophiolite sequence is a cross section through both the upper mantle and the oceanic crust. Credit: K. Cantner, AGI.

“Our loop drive through the high Hajar Mountains boasted excellent exposures of every oceanic crustal layer. One good exposure of the sequence of mantle rocks is found in the hills surrounding Oman’s capital city Muscat. They consist of a variety of peridotite called harzburgite, which is the pyroxene-depleted residue left behind after basaltic magma is extracted. That extracted magma forms the oceanic crust, whose characteristic rock sequence is, from bottom to top: 1) dark, layered gabbro overlain by massive gabbro (the intrusive equivalent of basalt that comprises solidified magma chambers); 2) sheeted basaltic dikes (the conduits that transported lava from the magma chambers up to the ocean floor); and 3) bulbous pillow lavas, which form when basalt erupts directly into seawater.

Slumgullion: Colorado's natural 'lab' offers insights into landslides worldwide

Mon, 09 Apr 2018 14:35:55 -0400

The enormous Slumgullion landslide in southwestern Colorado has been moving — sometimes imperceptibly slowly — every day for some 300 years. Credit: William Schulz, USGS.

In southwestern Colorado, a centuries-old “laboratory” looks out on the snowy peaks of the Lake City Caldera in a remote section of the San Juan Mountains. The lab’s scientists don’t wear white coats, but Gore-Tex and hiking boots, and they don’t work inside a building but on a 6.8-kilometer-long mishmash of red, brown and yellow earth topped with boulders, ponds and tilted spruce. Early settlers to the region called the mass Slumgullion, after an “everything-but-the-kitchen-sink” stew, with “slum” being an old word for “slime” and “gullion” an English term for “cesspool.”

From farm to filter: Restored wetlands remediate nitrogen pollution

Mon, 09 Apr 2018 11:21:45 -0400

Bottomland hardwoods are a predominant wetland type in the Mississippi Alluvial Valley, the historic floodplain and valley of the lower Mississippi River. Credit: U.S. Fish and Wildlife Service.

Nitrogen giveth and nitrogen taketh away: It’s been estimated that roughly half of the world’s population today could not exist without nitrogen fertilization. Although land area on Earth remains roughly the same on human timescales, population continues to rise, requiring more intensive and rigorous use of existing agricultural land and the creation of more agricultural lands to meet the ever-growing demand for food. One way humanity has supported population growth is through the manipulation of nitrogen, a limiting nutrient in terrestrial ecosystems. In 1913, the advent of the Haber-Bosch process, which artificially converts nitrogen gas to bioavailable ammonia, revolutionized access to nitrogen and all but eliminated nitrogen limitation in terrestrial ecosystems. Now, nitrogen fertilizers are often heavily applied to croplands to increase plant growth and productivity.

Geomedia: Books: Solar eclipses past, present and future

Mon, 09 Apr 2018 10:54:25 -0400

American Eclipse: A Nation's Epic Race to Catch the Shadow of the Moon and Win the Glory of the World, by David Baron, Liveright/W.W. Norton, Paperback, 2018, ISBN 9781631494550.

On Aug. 21, 2017, a total solar eclipse traversed across the United States, from the western coast of Oregon to the eastern shores of South Carolina. I witnessed about one minute and 50 seconds of totality from Salem, Ore., where the skies were unusually clear — despite the wildfires then raging around the West. In eclipse parlance, totality refers to the period when the moon — which, in the most mind-blowing of cosmic coincidences, just happens to be the same angular size in the sky as the sun — completely blocks the sun’s bright disk and reveals the tenuous outer solar atmosphere known as the corona.

Earth's "hum" heard at ocean bottom

Tue, 03 Apr 2018 16:09:49 -0400

An ocean-bottom seismometer is deployed in the Indian Ocean. Credit: RHUM-RUM experiment/Meteor Cruise

Lapping waves or crashing surf may come to mind for most people when they imagine the sounds of the ocean. But the ocean has other voices as well, including one produced by interactions of waves with the seafloor along the continental slope. Unlike waves on the shoreline, this steady, low sound, or “hum,” is inaudible to the human ear and has even proven difficult to detect in recordings made by ocean bottom seismometers (OBS). But in a new study in Geophysical Research Letters, researchers analyzing OBS data have now clearly identified the hum for the first time, which may allow it to be used to develop a better picture of Earth’s interior structure.

Geologic Column: Over the hills and far away

Tue, 27 Mar 2018 12:31:26 -0400

Credit: Sam Romilly CC BY-SA 2.0

Tom, he was a piper’s son, He learnt to play when he was young, And all the tune that he could play Was “Over the Hills and Far Away."

Getting there and getting around the Causses

Fri, 23 Mar 2018 12:16:19 -0400

Visitors to the Causses region can find places to stay in any of dozens of charming towns throughout the region. Credit: both: Callan Bentley.

Toulouse is the best gateway to the Causses region. Toulouse-Blagnac Airport hosts plenty of flights to connecting cities in Europe, but no direct flights from the United States. Rent a car at the airport and head north to explore the region. The main highway going north to the Causses is well maintained, with fueling stations along the way that offer everything a traveler might need, including showers. Figuring out how to pay for gasoline was tricky — but that’s part of the adventure of travel.

Pairing geoheritage and economic development: China's Guizhou Province offers a modern model

Thu, 22 Mar 2018 14:00:53 -0400

Guizhou Province is known for its stunning karst topography. Credit: ©iStockphoto.com/KingWu.

As I admired an immaculately preserved colony of 230-million-year-old crinoids lying next to an equally impressive skeleton of a sharp-toothed ichthyosaur at China’s Guanling Fossil Group National Geopark, I thought back to family trips to North American national parks during my youth. The natural wonders I saw on those trips strongly influenced my career choice and shaped my perception of how humans fit into Earth’s long history. Today, even after more than 35 years spent studying the Earth, every visit to a spectacular natural site like this one in Guanling still engenders the same excitement and insight I had as a youngster.

Benchmarks: April 4, 2011: Air France Flight 447 wreckage found using modern oceanography tools

Tue, 20 Mar 2018 14:32:27 -0400

On June 1, 2009, Air France flight 447 (AF447) from Rio de Janeiro to Paris crashed in the Atlantic Ocean near the mid-ocean ridge, killing all 228 passengers and crew aboard. Credit: BEA, France, bea.aero.

In the early morning hours of March 8, 2014, Malaysia Airlines flight 370 (MH370), en route from Kuala Lumpur to Beijing, lost communication with air traffic control during the transition between Malaysian and Vietnamese air space. It then disappeared, along with all 239 people aboard.

Down to Earth With: Conservation engineer Emily Pidgeon

Mon, 19 Mar 2018 14:29:28 -0400

Emily Pidgeon, senior director of the oceans and climate program at Conservation International, led the formation of the Blue Carbon Initiative, an international nonprofit organization that works to mitigate climate change by protecting coastal ecosystems. Credit: Sarah Derouin.

“I can be a very blunt object,” says Emily Pidgeon, describing how she moves through the world and how she approaches her work. Her Australian accent, drawling yet punctuated, rises above the din of the lunch crowd at a café. She pauses a moment, and declares herself a larrikin. “Do you know that word, larrikin?” She explains that Australians have a larrikin culture — they’re troublemakers, but in a good way. “We have a healthy disrespect for authority,” she says, sipping her tea.

Chemical tipping point triggers eruptive transitions

Mon, 19 Mar 2018 14:23:18 -0400

Mount Pinatubo in the Philippines is most famous for the explosive phases of its 1991 eruption, but the months-long eruption was also punctuated by gentler periods of oozing lava. Credit: U.S. Geological Survey.

During an eruption, some volcanoes vacillate unpredictably between effusive and explosive behavior. New research has identified a chemical tipping point in some magmas that may trigger the transition between such mild and violent eruptive cycles.

No river meant no floods for ancient Indus settlements

Mon, 19 Mar 2018 14:20:46 -0400

The path of the Ghaggar-Hakra paleochannel can be seen in this composite Landsat image. The modern Sutlej River may have flowed through the paleochannel prior to the development of Indus Civilization cities. Credit: P.J. Mason/S. Gupta, Imperial College London; Landsat imagery courtesy of NASA Goddard Space Flight Center and U.S. Geological Survey.

Large Middle Eastern rivers like the Nile, Tigris, Euphrates and Tiber were critical for the development of early urban societies in Egypt, Mesopotamia and Ancient Rome. And researchers have long thought that the rise, and eventual decline, of cities in the ancient Indus Civilization, which spread across about 1 million square kilometers of what’s now northwestern India and Pakistan from roughly 4,600 to 3,900 years ago, also depended on major rivers, namely those emerging from the Himalayas. But a new study looking at river sediments from the time of the civilization and earlier suggests that wasn’t the case for every ancient Indus city; some may have benefited from being farther away from large rivers and their periodic floods.

Oldest "Third Pole" ice core recovered

Mon, 19 Mar 2018 14:17:39 -0400

Lonnie Thompson cuts an ice core retrieved from the Guliya Ice Cap in the Kunlun Mountains in Tibet. Credit: Giuliano Bertagna/Byrd Polar and Climate Research Center.

Holding massive reservoirs of ice, high-altitude glaciers, such as those in the Himalayas, are sometimes referred to as Earth’s “Third Pole.” The Guliya Ice Cap, on the Tibetan Plateau, has now produced the oldest ice ever drilled outside the Arctic or Antarctica.

Measuring earthquakes using fiber-optic cables

Mon, 19 Mar 2018 14:09:33 -0400

Nathaniel Lindsey of the University of California, Berkeley, buries fiber-optic cable in a trench near Fairbanks, Alaska, to record earthquake seismicity. Credit: left: Anna Wagner; right: Nathaniel Lindsey.

Fiber-optic cables crisscross the world, ferrying digital data and enabling internet access and telecommunication. In a new study, published in Geophysical Research Letters, researchers tested whether fiber-optic cables can also be used to detect and measure earthquakes.

Surveying forests from afar

Mon, 19 Mar 2018 14:06:44 -0400

Researchers used airborne imaging and spectroscopic techniques to study the diversity of forests in Switzerland's Laegern Mountains. Credit: UZH.

Traditional surveys of forest health and diversity take hours of hiking and sampling by scientists who can only cover relatively small areas. Satellites, meanwhile, can survey large swaths of land, collecting information about forests in a fraction of the time that a ground survey might take. But the resolution and types of satellite data available don’t always allow for detailed studies. Now, a team of ecologists is staking out the middle ground by developing airborne laser scanning techniques to create high-resolution maps of tree species diversity to monitor changes in forest ecosystems.

Globe-trotting bacteria found at both poles

Mon, 19 Mar 2018 14:04:01 -0400

University of Tübingen geoscientist Julia Kleinteich collects water samples in Antarctica. Credit: Daniel Farinotti.

The Arctic and Antarctica, separated by more than 15,000 kilometers, may be geographic opposites but they share many similarities, including their diverse arrays of bacteria and other microscopic life forms. A new study looking at the DNA of bacteria from both poles has found remarkable similarities between the two regions’ bacterial diversity, including some of the same species.

LIP split by South Atlantic breakup was sourced from deep

Thu, 15 Mar 2018 15:51:47 -0400

Massive volumes of rock called large igneous provinces (LIPs) have formed many times throughout Earth’s history, fed by some of the planet’s mightiest volcanic events. The volcanic eruptions, sometimes lasting millions of years and pouring hundreds of thousands of cubic kilometers of lava onto the surface, have influenced continental breakups, past climate change and mass extinction events. For everything that’s known about LIPs, however, many questions about them remain, including how far below the surface the erupted magma originate. In a recent study, researchers report that the origins of the Paraná-Etendeka LIP likely lay deep in Earth’s interior.

Carbon emissions spike when continents rift

Wed, 14 Mar 2018 13:40:14 -0400

Part of the East African Rift, the largest continental rift on Earth today, in southern Kenya as seen from the International Space Station in 2012. Many of the linear features running from the bottom-left (north) to top-right (south) are scarps formed by faulting associated with the rift. Credit: NASA.

The vast majority of Earth’s carbon is stored in the planet’s interior. This buried carbon is not isolated from the surface over geologic timescales, however; some of it is released back into the atmosphere as carbon dioxide and other gases when volcanic eruptions occur above subduction zones or island arcs. In a couple of new studies, researchers have identified another major component in the global carbon cycle: continental rift faults. Such faults, like those found along the East African Rift today, may contribute even more carbon dioxide to the atmosphere at times than volcanoes.

Down to Earth With: Award-winning sci-fi novelist Kim Stanley Robinson

Fri, 09 Mar 2018 12:03:41 -0500

Kim Stanley Robinson. Credit: Gloria Robinson.

Don’t let Kim Stanley Robinson fool you. He may know a lot about the geography of Mars and ocean acidification, but he’s no scientist. He’s an award-winning science fiction novelist. Yet the science in his books is so convincing that many fans can’t help but be duped.

Gyres spin up, currents get muddled

Thu, 08 Mar 2018 11:37:13 -0500

In the Weddell Sea Gyre, one of two clockwise-spinning circulation patterns in the Southern Ocean, warming has accelerated the spinning. Recent research suggests this acceleration — and the warmer, faster-moving Antarctic Circumpolar Currrent and Circumpolar Deepwater that result — may trigger the development of smaller, shorter-lived polynyas like those observed over the past two years. Credit: K. Cantner, AGI.

In addition to polynya formation and warming-induced surface freshening, other factors may also impact open-ocean convection in the Southern Ocean. The warming atmosphere is shifting global climatic zones and their associated wind fields poleward in both hemispheres. In the Weddell Sea Gyre, one of two clockwise-spinning circulation patterns in the Southern Ocean, this shift has resulted in a dramatic increase in wind stress curl (the strength of the wind’s influence on ocean water flow) over the past two years.

Disrupting the deep: Ocean warming reaches the abyss

Thu, 08 Mar 2018 11:29:52 -0500

SOCCUM Project, Hannah Zanowski, CC BY 2.0

Seventy-one percent of our planet is covered by ocean, and these basins contain 97 percent of Earth’s near-surface water. The ocean lies at the heart of the global climate system, shaping all parts of our environment, even in the deepest continental interiors. So as the ocean goes, so goes the planet — and the ocean is warming.

Geomedia: On the Web: How will melting ice impact your city?

Thu, 08 Mar 2018 10:07:44 -0500

Gradient fingerprint mapping can be used to determine how the loss of distant land-ice will impact local sea-level rise. These gradient maps show how ice loss from the Greenland Ice Sheet (left) and Antarctica (right) will affect sea-level rise near New York City. Ice loss from areas colored red will have a larger impact on New York's local sea-level rise, while melting in blue regions will have little to no impact on sea-level rise in New York. Antarctic melting will affect New York far more than Greenland melting. Credit: Larour et al., Science Advances, November 2017.

The relationship between melting glaciers and rising sea levels is best described as: “It’s complicated.” A new online tool shows just how counterintuitive predictions of how melting land-ice will affect coasts can be.

Geologic Column: Pie on Pi Day, and Einstein's lesser-known legacy

Fri, 02 Mar 2018 06:01:52 -0500

MIT's Experimental Study Group often bake pie as a way to celebrate Pi Day. Credit: Evan Shelhamer, CC BY 2.0.

March hosts a number of special days: St. Patrick’s Day, Johnny Appleseed Day, the Spring Equinox and, one of my favorites, March 14, which is both the birthday of the father of modern physics, Albert Einstein, and also Pi Day, which celebrates the mathematical constant 3.14 that features in some of Einstein’s equations.

Getting There & Getting Around Corsica

Thu, 01 Mar 2018 15:16:33 -0500

After a relaxing day of sun and sand, you can enjoy a divine dinner at one of the many colorful cafes that line Corsica's old town alleyways. Credit: Terri Cook and Lon Abbott.

The two largest of Corsica’s four airports, Ajaccio (AJA) and Bastia (BIA), are located on the island’s southwestern and northeastern coasts, respectively. There are no direct flights from the U.S. to Corsica, so it’s usually cheapest and most convenient to fly into Paris and then catch a 1.5-hour flight to the island. Air France and Air Corsica operate connecting flights year-round from most major French cities. During the bustling summer months, other carriers, including the budget airlines EasyJet and Ryanair, offer direct service from numerous European cities. If you prefer to arrive by ferry, several lines, including Corsica Ferries and Moby Lines, offer year-round transport from Marseille, Nice and Toulon, as well as summer routes from several Italian ports.

Travels in Geology: Corsica: A fusion of cultures on the Mediterranean's most mountainous isle

Thu, 01 Mar 2018 14:56:09 -0500

The sun's last rays bathe the west coast of Corsica, whose spectacular geology and easygoing culture are a fusion of Italian, French and other Mediterranean influences. Credit: Terri Cook and Lon Abbott.

Last summer, after trekking for a month with my son across the cool and rainy Alps, I found myself craving warm sunshine and long, sandy beaches. So we headed to Corsica, the Mediterranean’s most mountainous isle, whose narrow shoreline is dotted with gorgeous strips of white sand beaches. Best known as the birthplace of Napoleon Bonaparte, the island has a long history of Italian rule followed by nearly 250 years of French control, which it remains under today. The resulting culture combines the best attributes of both countries. The island’s rugged topography is also a blend, the consequence of rocks of very different ages and origins being thrust together during one of Earth’s great tectonic upheavals. Together, these fusions have created an irresistible mixture of stunning scenery, beautiful beaches, captivating cultural attractions and mouthwatering cuisine that is distinctly Corsican.

Benchmarks: March 29, 1912: Scott's South Pole Journey Ends in Death

Tue, 27 Feb 2018 14:31:07 -0500

This map shows the routes taken by the teams of Roald Amundsen and Capt. Robert F. Scott from their bases on the edge of the Ross Ice Shelf across the Antarctic Plateau to the South Pole in 1911–1912. Credit: Ryan Fogt/American Meteorological Society/BAMS.

The epic tale of the race between Norway and Britain to be the first to reach the South Pole — and its tragic conclusion with the deaths of British team members in February and March 1912 — is well known. But the details of what happened on the ice, of what went wrong for the British expedition, have continued to be discussed and debated since the bodies of Capt. Robert Falcon Scott and his four crewmates were discovered the following summer. Several recent studies on the Antarctic climate and on the questionable behavior of Scott’s second-in-command are casting new light on the outcome of the expedition.

Geomedia: Books: "Aerial Geology": A stunning and informative addition to any coffee table

Tue, 27 Feb 2018 14:22:50 -0500

My fellow EARTH Magazine contributor Mary Caperton Morton is the author of “Aerial Geology,” a beautiful and massive tome that profiles a hundred geologically interesting locations across North America. Mary was kind enough to forward me a copy for review, and I was delighted to flip through its gorgeous pages. It’s a visual feast, with a mix of satellite imagery, aerial photography and ground-based photos. Each site is allotted two to four pages for photos and Mary’s written descriptions, which are sometimes augmented by excellent schematic illustrations by the talented Kat Cantner, the illustrator for EARTH and the American Geosciences Institute (which publishes EARTH).

Geomedia: Books: "Half-Earth" is only half-compelling

Tue, 27 Feb 2018 14:14:31 -0500

"Half-Earth: Our Planet's Fight for Life," Edward O. Wilson, Liveright, 2017 (paperback), ISBN-13: 978-1631492525

Edward O. Wilson, professor emeritus and honorary curator in entomology at Harvard, is a scientist of acclaim and renown, a naturalist and experimentalist who has made astounding discoveries about the natural world. These discoveries range from small details about ant communication to much larger ideas related to sociobiology, the co-evolution of genes and culture, island biogeography and biophilia, for example. His work is widely known, in large part, because he’s a talented and prolific writer, and he has twice won the Pulitzer Prize.

Down to Earth With marine geoscientist Harold Tobin

Tue, 27 Feb 2018 13:38:40 -0500

Harold Tobin, a marine geophysicist at the University of Wisconsin-Madison, aboard the research vessel Marcus G. Langseth, collecting a marine seismic reflection survey of the Cascadia Subduction Zone off the coast of Washington state. Credit: Jackie Caplan-Auerbach.

As a boy growing up on the East Coast, Harold Tobin loved being outdoors but was not all that excited by geology or the region’s ancient rocks. But the catastrophic eruption of Washington state’s Mount St. Helens in 1980, when Tobin was 15, and the notion that tectonic plates must be moving beneath the Pacific Northwest, captured his imagination. A few years later, while a student at Yale University, he volunteered as a summer intern at Mount St. Helens National Volcanic Monument. That experience, along with his undergraduate curriculum, convinced Tobin to become a geologist.

Ice (Re)Cap: March 2018

Tue, 27 Feb 2018 13:27:15 -0500

A new map shows the geothermal heat flux beneath Antarctica in detail. Credit: Martos et al., Geophysical Research Letters, November 2017.

Lakeshore shape influences lake-effect snow

Tue, 27 Feb 2018 13:22:45 -0500

The Tug Hill region east of Lake Ontario in Upstate New York is one of the most snow-prone areas in the U.S. as a result of lake-effect snow systems that blow in from the west. Credit: University of Utah.

On Dec. 11, 2013, Upstate New York’s Tug Hill region received more than 100 centimeters of snow in 24 hours. And annually, the region, which covers more than 5,000 square kilometers to the east of Lake Ontario, can see up to five times that amount. In comparison, Toronto, on the northwestern coast of the lake, averages less than 125 centimeters of snow each year.

Gettysburg rocks tell battlefield tales

Tue, 27 Feb 2018 13:18:04 -0500

Since the late 19th century, Civil War battlefield landscapes have changed. Some have been plowed under and developed, while elsewhere, woods have been cut down or become overgrown. But the rocks that dotted those battlefields from Gettysburg to Mississippi largely still stand. Historians are now using the steadfast boulders and ridges seen in the backgrounds of 154-year-old battlefield photographs to learn more about the skirmishes that took place at certain sites.

Spawning salmon engineer landscapes

Fri, 23 Feb 2018 11:16:59 -0500

Spawning sockeye salmon swim in a stream in Alaska. Credit: Katrina Mueller, U.S. Fish and Wildlife Service.

All animals depend on their ecosystems for habitat. And, in turn, many animals impact their ecosystems by engineering the landscape to suit their needs. Beavers provide an iconic example of ecosystem engineering when they build dams, which influence streams and wetlands. The engineering efforts of salmon, meanwhile, can even shape the bedrock of the watersheds in which they live, according to a recent study that modeled the evolution of those watersheds over several million years.

How do earthquakes impact landslides?

Thu, 15 Feb 2018 14:54:55 -0500

The town of Qushan in Beichuan County, China, was destroyed by strong shaking from the 2008 Wenchuan earthquake and subsequent catastrophic landslides. Credit: David Wald, USGS.

Sensitive instruments installed on and near the slow-moving landslide in Maca, Peru, have allowed scientists to observe the response of the landslide to earthquakes: information that can help researchers predict hazards from other slow-moving landslides in the region and perhaps around the world. But scientists are wondering whether the findings could also shed light on the triggering of fast-moving landslides by earthquakes.

Isotopes reveal sources of centuries-old alabaster artifacts

Thu, 15 Feb 2018 14:45:17 -0500

Close-up of a 14th-century alabaster panel in the Louvre Museum in Paris. Credit: Wolfram Kloppmann.

When geologists think of alabaster, they likely envision blocks of gypsum, its main mineral constituent; when art historians hear the word, statues crafted from the soft rock may come to mind. A new study focused on the sources of centuries-old alabaster artworks has geologists thinking about art history, and art historians pondering geochemistry. In the study, published in Proceedings of the National Academy of Sciences, researchers used isotope fingerprinting along with historical records to tie medieval and Renaissance alabaster sculptures to the quarries from which their materials were excavated.

Meteorite impacts may have kick-started ancient subduction

Thu, 15 Feb 2018 14:41:27 -0500

Frequent impacts from large meteorites during the Hadean Eon could have instigated temporary episodes of subduction and active plate tectonics on Earth. Credit: NASA's Goddard Space Flight Center Conceptual Image Lab.

Earth in the Hadean Eon, between 4.56 billion and 4 billion years ago, was much too hot to support active plate tectonics as we know it today, where cold, established plates slowly march around Earth. Yet some evidence, including from tiny zircon crystals dating to the Hadean, has suggested that a form of plate tectonics was active by about 4.1 billion years ago — about a billion years before many researchers think modern plate tectonics started. The mechanisms that could have initiated and sustained early tectonics are unclear, but according to a new study, constant bombardment of early Earth by meteorites could have triggered temporary bursts of early tectonism.

Coal formation nearly froze Earth

Thu, 15 Feb 2018 14:38:19 -0500

Vast deposits of coal, such as this seam in Kentucky dating to the Middle Pennsylvanian, formed during the Carboniferous Period, and drew down atmospheric carbon dioxide concentrations. Credit: James St. John, CC BY 2.0.

Burning coal releases carbon dioxide, which warms the planet when the gas escapes into the air. On the flip side, coal formation sequesters carbon dioxide removed from the atmosphere by plants, which contributes to global cooling as the planet’s greenhouse gas blanket thins. According to new research, so much carbon was removed from the atmosphere in the Carboniferous Period, when most of Earth’s coal reserves formed, that the planet became almost completely covered in ice.

Greenland's growing deltas: Combining historical and modern imagery to decode change in a telltale Arctic landscape

Fri, 09 Feb 2018 14:50:54 -0500

The coast of Greenland has more than 100 pristine deltas formed by rivers draining from the Greenland Ice Sheet into the sea, interspersed amid the coast's irregular geometry of fjords and icy bays. Credit: Anders Anker Bjørk.

Enormous quantities of fine sediment, sand and rock are carried downstream by rivers flowing off the Greenland Ice Sheet. Where these rivers meet the ocean, they deposit the sandy, coarse part of their sediment loads, forming textbook fan-shaped deltas. Credit: Nicolaj Krog Larsen.

Greenland’s rivers are impressive, with fast, powerful flows of turbulent, milky waters descending from glaciers of the Greenland Ice Sheet, which loom only a few kilometers upstream. Enormous quantities of fine sediment known as “glacier flour,” as well as sand and rock are discharged into and carried downstream by these rivers. The grinding action of the sediment-laden torrents is formidable and carves beautiful smooth sculptures in the solid granite bedrock. From the riverbank, the noise is overwhelming as the loud crashing of the turbulent water flow combines with a rumbling undertone from rocks colliding with the river bottom.

Double-dip La Nina blamed for Colorado's dry winter

Mon, 05 Feb 2018 15:12:00 -0500

In January 2017, skiers at Wolf Creek Ski Area in southern Colorado were enjoying a base snow depth of more than 350 centimeters — enough snow to cover most rocks and other obstacles. But this year, as of mid-January, the runs were much sparser, with the base barely clearing 100 centimeters. Powderhorn Resort in western Colorado was so bereft of snow that it had yet to open in mid-January — a month behind their usual December opening. Statewide the snowpack is slim enough to worry not only skiers, but also the state’s climatologists and water resource managers, who held a Water Availability Task Force (WATF) meeting on Jan. 18 to discuss the state’s snowpack and water outlook.

No river meant no floods for ancient Indus settlements

Mon, 22 Jan 2018 16:06:40 -0500

This remnant of a street was excavated at the site of the Indus Civilization urban center of Kalibangan, which was situated along the Ghaggar-Hakra palaeochannel. Credit: S. Gupta, Imperial College London

Geologic Column: Travels with Claudia: Rediscovering America

Tue, 16 Jan 2018 21:03:31 -0500

Fred's road bike traveled across the U.S. (including to the Badlands) with him and Claudia last summer. Credit: Claudia Schwab.

Claudia and I have been traveling together since we got married in February 1965. That summer and the following summer, she graciously agreed to be my assistant during summer fieldwork seasons in the Tetons and the Wyoming Overthrust Belt near Jackson Hole. By 1967, she resigned as my field assistant, but, thankfully, held on to her position as wife, traveling partner, photographer and biographer. Recently, she talked me into renewing our ties with the broader U.S. beyond our doorstep, so after spending the last dozen Julys in France watching the Tour de France, we spent the summer of 2017 rediscovering America, including our original fieldwork locales.

Travels in Geology: Las Vegas: The scenery beyond the slots

Tue, 16 Jan 2018 20:20:31 -0500

Mega-resorts along the Las Vegas Strip make a convenient base for exploring the area's spectacular scenery. Credit: Terri Cook and Lon Abbott.

Known for its dazzling neon lights, mega-casinos with nonstop gambling, high-end shopping and restaurants, and marquee shows, Las Vegas is an unapologetic icon of American hedonism — and one of the country’s top tourist destinations. Our eagerness to visit Sin City, however, had nothing to do with spinning roulette wheels or the clanging slot machines that would quickly claim our $10 gambling quota. We flew to Las Vegas to see the spectacular scenery beyond the slots: southern Nevada’s craggy limestone peaks, colorful sandstone canyons and enormous conservation areas that, despite the searing desert heat, harbor a tremendous diversity of plants and wildlife. From soaring summits and graceful bighorn sheep to prehistoric petroglyphs, we couldn’t wait to experience all that this desert oasis has to offer.

Mediterranean drawdown may have caused burst of volcanism

Tue, 16 Jan 2018 12:26:29 -0500

The Strait of Gibraltar, the seaway connecting the Atlantic Ocean to the Mediterranean Sea between Africa and Europe, closed roughly 6 million years ago, initiating the Messinian Salinity Crisis. Credit: CC0

Between 5 million and 6 million years ago, during an event known as the Messinian Salinity Crisis (MSC), large amounts of seawater evaporated from the Mediterranean Sea leaving massive salt deposits in the basin. How much the sea surface dropped during the MSC is debated, but in a new study in Nature Geoscience, researchers suggest that a large, kilometer-scale drawdown of the Mediterranean Sea may explain not just the thick salt deposits but also a pulse of magmatic activity around the region that occurred at the same time as the MSC.

Benchmarks: February 12, 1986: France and the U.K. sign the Treaty of Canterbury, paving the way for the Chunnel

Fri, 12 Jan 2018 14:57:53 -0500

The Chunnel runs almost entirely through the West Melbury Marly Chalk. By the late 19th century, this layer had already been identified as the most suitable option for tunneling based on its strength, low permeability, ease of excavation, and depth and continuity below the channel floor. Credit: K. Cantner, AGI.

Since the tunnel connecting Britain and France beneath the English Channel opened in 1994, more than 390 million people and 320 million metric tons of goods have made the 50-kilometer subterranean trip. The Channel Tunnel, or Chunnel, which is actually three separate tunnels — two for rail traffic and one for maintenance — thus plays a major part in the countries’ economies, as well as in the broader European economy. Beyond that distinction, it has been memorialized in popular TV, movies and literature. And in recent years, the tunnel has taken on literal and symbolic significance as a gateway amid flows of refugees from strife-ridden parts of the world and in debates over immigration policy. The Chunnel has become so firmly embedded in the regional infrastructure and culture during the past quarter century that it is difficult to imagine it not being there today.

Looking under Lusi: Indonesian mud volcano linked to nearby volcanic complex

Fri, 12 Jan 2018 14:52:03 -0500

The Lusi mud eruption began in May 2006 and has continued unabated since. Currently, it spews about 80,000 cubic meters of mud per day. Credit: Adriano Mazzini/Lusi Lab Project.

On May 29, 2006, a massive mud eruption in East Java, Indonesia, began spewing as much as 180,000 cubic meters — the volume of 72 Olympic-sized swimming pools — of hot muddy debris each day from several vents, quickly burying nearby villages and forcing the relocation of more than 60,000 people. Almost 12 years later, the eruption, nicknamed Lusi, continues to produce more than 80,000 cubic meters of mud a day, and nobody knows how long the oozing will continue. In a new study, however, scientists have gotten the clearest look yet of the roots of the mud volcano and its possible connection to a nearby volcanic complex that may be driving the eruption.

Geomedia: Books: Putting 'Seeds on Ice' to protect crop diversity

Fri, 12 Jan 2018 14:48:22 -0500

"Seeds on Ice: Svalbard and the Global Seed Vault," Cary Fowler, Prospecta Press, 2016, ISBN: 9781632260574

“Tucked away, deep underground, in a frozen corner of the Scandinavian north is the safety net for our food supply. The Global Seed Vault, on the island of Spitsbergen in Norway’s Svalbard Archipelago and popularly known as the “doomsday vault,” shelters our most precious seeds from possible global catastrophe.

Fossil reefs show sea level rose in bursts

Fri, 12 Jan 2018 14:34:45 -0500

Off the coast of Texas, a collection of fossil coral reefs sits under 60 meters of water — relics from 20,000 years ago, when the sea surface was much lower than today. In a new study, researchers created high-resolution maps of the reefs that suggest they drowned as sea levels rose in rapid bursts — each lasting decades to centuries — instead of at a steady rate, as has long been assumed.

Ice age didn't freeze Florida's category 5 hurricanes

Fri, 12 Jan 2018 14:32:54 -0500

Seafloor sediment cores spanning the Younger Dryas (YD) into the warmer early Holocene (EH) suggest that, during the Younger Dryas about 12,000 years ago, sea-surface cooling (a), which tends to suppress hurricane formation, was less prominent near Florida than it was farther south in the tropics, near Barbados. The potential frequency (b) and maximum intensity (c) of tropical storms were also higher by Florida. Credit: Toomey et al., Geology, October 2017.

A new study looking at turbidites off the coast of Florida shows that category 5 hurricanes may still have battered Florida even during the chilly conditions of the Younger Dryas, about 12,000 years ago, at the end of the last ice age.

Mineral Resource of the Month: Titanium

Fri, 12 Jan 2018 14:15:59 -0500

Dark layers in these heavy mineral sands in South Carolina are composed mainly of rutile and ilmenite. Credit: USGS.

by George M. Bedinger, USGS mineral commodity specialist

Mineral Resource of the Month: Zinc

Thu, 11 Jan 2018 15:45:54 -0500

Sphalerite is the ore mineral from which most of the world's zinc is recovered. Credit: Scott Horvath, U.S. Geological Survey.

by Christine Thomas, USGS mineral commodity specialist

Mineral Resource of the Month: Strontium

Thu, 11 Jan 2018 15:27:14 -0500

by Sheryl Singerling, USGS mineral commodity specialist

PRODUCTION

GEOLOGIC OCCURENCE

Two strontium-bearing minerals, celestite (strontium sulfate, SrSO4) and strontianite (strontium carbonate, SrCO3), contain strontium in sufficient quantities to make recovery practical. Celestite occurs much more frequently and is the primary source of the world’s supply of strontium. Celestite occurs as crystals and as massive or fibrous aggregates in sedimentary rocks. It often displays a delicate blue color owing to the presence of impurities. Celestite can occur in bedded evaporite deposits in conjunction with gypsum, anhydrite and halite. It can also occur in cavities within carbonate rocks where it is precipitated from strontium-bearing groundwaters or brines.

Mineral Resource of the Month: Silicon

Thu, 11 Jan 2018 14:59:24 -0500

Silicon may be the second-most abundant element on the planet, but it's rarely found alone in nature; instead it is usually found in silicate minerals or oxide minerals such as quartz, shown here. Credit: ©StoneTrust, Inc./ESW Image Bank.

by Emily Schnebele, USGS mineral commodity specialist

Mineral Resource of the Month: Fluorspar

Thu, 11 Jan 2018 13:48:43 -0500

Mined in 1991, this is a matrix-free specimen of highly transparent, light-blue fluorite crystals, with touches of purple. Fluorite is an important industrial mineral used in a wide variety of chemical, metallurgical and ceramic processes. Credit: Rob Lavinsky, iRocks.com, CC-BY-SA-3.0.

By Michele E. McRae, USGS mineral commodity specialist

Congress mulls options for abandoned mines legislation

Wed, 10 Jan 2018 10:48:10 -0500

Cement Creek near Silverton, Colo., flows orange on Aug. 12, 2015, after a large amount of acid mine drainage leaked a week prior from the Gold King Mine, which was abandoned in 1922. Credit: U.S. Geological Survey.

Amid the well-publicized discussions over healthcare, tax reform, the federal budget and disaster aid in summer and fall 2017, a quieter conversation over mining legislation reform was also going on in Congress. Democrats and Republicans in both chambers introduced legislation concerning abandoned mine lands (AML) in the current congressional session, and while no new bills have been passed, discussions continue on the contentious subject.

Beavers preserve wetlands in water-stressed areas

Wed, 10 Jan 2018 10:44:23 -0500

Once considered detrimental to ecosystems and nuisances where, for example, dams flooded farmland, beavers have been rhetorically touted in recent years as a potential boon for wetland health and water conservation. Anecdotal accounts and qualitative findings have suggested beavers improve water quality and availability in drought-stressed ecosystems, but just how much influence they have was not known. In new research, scientists have examined two creeks in Nevada to directly measure how effective beaver dams are at slowing water flows and storing water through the dry summer months.

Isotopes suggest ancient turquoise mine was prolific

Wed, 10 Jan 2018 10:37:55 -0500

This turquoise mosaic piece from a precolonial site in Arizona has isotope ratios consistent with geologic samples from Canyon Creek. Credit: Saul Hedquist.

Few minerals are more iconic in the Desert Southwest than turquoise. The blue-green gemstone, which offers a stark contrast to the dusty red southwestern deserts, has been coveted for thousands of years by indigenous peoples, conquering Spaniards and now by a growing market around the world. Despite its past and present cultural significance, especially among indigenous populations, little is known about the early history of turquoise mining. Researchers have now uncovered previously unknown details about a historic turquoise mining site in Arizona that suggest it was more prolific than once thought.

Unexpected nanoparticles trace coal pollution

Wed, 10 Jan 2018 10:34:44 -0500

U.S. Fish and Wildlife Service and Duke Energy representatives sample coal ash deposited on the bank of the Dan River in North Carolina days after a massive coal ash spill in 2014. Credit: Steve Alexander, USFWS.

Coal burning produces an array of chemicals and particulates that, when released into the atmosphere, contribute to pollution, poor air quality and threats to public health. Measurements of particulate air pollution typically focus on particles called PM2.5, which have diameters of 2.5 micrometers or less. This group includes nano-sized particles, although these bits of minerals, dust and organics often go undetected because of their tiny size. In a new study, researchers sampling a coal ash spill have unearthed a type of nanoparticle not previously known to be produced by burning coal. While the particles might be useful in detecting pollution problems, they may also have consequences for human and environmental health.

Mediterranean tsunami record may be overreported

Tue, 09 Jan 2018 14:20:55 -0500

Large, out-of-place boulders found inland, like these blocks along Algeria's Tipaza Coast, are often taken as evidence of past tsunamis. Credit: C. Morhange.

Tsunamis are one of the most destructive natural hazards on Earth, sometimes even upstaging the major earthquakes that send the waves surging across entire ocean basins. Knowing when, where and how severely tsunamis have struck coastlines in the past is valuable for countries trying to prepare for the impacts of future tsunamis. But distinguishing tsunami deposits in geologic paleorecords from deposits left by more common storm waves is notoriously difficult. Researchers recently highlighted this challenge by taking a hard look at tsunami- and storm-wave records around the Mediterranean Sea over the last 4,500 years. The findings may serve as a cautionary tale for scientists interpreting tsunami records elsewhere in the world.

Small warm ponds: Ideal incubators for first life?

Tue, 09 Jan 2018 14:15:29 -0500

If a meteorite bearing nucleotides happened to splash down into a small, warm pond early in Earth's history, the nucleotides could have been in an ideal environment in which to link together into RNA. Credit: Callan Bentley, 2017.

The first embers of life are thought to have emerged on Earth between 4.5 billion and 3.7 billion years ago, but how and where the initial sparks arose remains a mystery. Two leading theories suggest that the first self-replicating molecules — a necessity for life — may have gotten a start either in deep-ocean hydrothermal vents or in small warm ponds on land. In a new study, researchers suggest that the wet-dry cycles occurring in small, seasonal ponds would have made a better natural incubator.

Down to Earth With: Wildfire meteorologist Craig Clements

Tue, 09 Jan 2018 14:06:19 -0500

Meteorologist Craig Clements is an associate professor and director of the Fire Weather Research Laboratory at San Jose State University. Credit: D. Schmidtz.

Not many people are able to combine their work and hobbies the way Craig Clements, a meteorologist at San Jose State University in California, has. “I was always interested in mountain weather,” he says. “I got into meteorology through my interest in mountaineering and climbing.”

Dividing line: The past, present and future of the 100th Meridian

Tue, 09 Jan 2018 13:30:45 -0500

The Great Plains are well known for their sweeping grasslands, which, to the east, eventually turn into great farms, and, to the west, give way to deserts and mountains. Credit: ©iStockphoto.com/Danielrao.

In 1878, without benefit of the Landsat program, GPS or Google, and just a decade after the creation of the National Weather Service, John Wesley Powell first advanced the idea that the climatic boundary between the United States’ humid East and arid West lay along a line “about midway in the Great Plains” — almost exactly 100 degrees longitude west of the prime meridian in Greenwich, England. This line, the 100th meridian, runs from pole to pole and cuts through six U.S. states, forming a partial boundary between Oklahoma and Texas. The 100th meridian also corresponds roughly to the 600-meter elevation contour as the land rises from the Great Plains toward the Rockies.

A flammable planet: Fire finds its place in Earth history

Tue, 09 Jan 2018 07:07:24 -0500

For hundreds of millions of years, wildfires have shaped the planet. Credit: Naomi Kelly.

We owe Earth as we know it to fire. Fire-prone ecosystems cover 40 percent of the land surface today, and fires play a key role in maintaining many of the world’s major biomes, including grasslands, savannas, shrublands and boreal forests. It’s thought that global forests would double in extent in the absence of fire.

Down to Earth With Kateryna Klochko

Tue, 02 Jan 2018 14:52:45 -0500

Kateryna Klochko headshot. Credit: Carnegie Institution of Washington.

Kateryna Klochko made a splash in the ocean geochemistry world as a doctoral student at the University of Maryland in College Park. She had been in the U.S. for only a few years, following a long journey from her native Ukraine. Yet she was about to challenge paradigms.

Driftwood reveals ancient Arctic currents and sea-ice levels

Thu, 28 Dec 2017 12:37:35 -0500

Driftwood frozen into sea ice can be transported around the Arctic, eventually collecting on distant shores such as on the island of Phippsøya in Svalbard, which lies to the east of northern Greenland. Credit: Marc Macias-Fauria

Arctic driftwood up to 12,000 years old is giving scientists a better understanding of how ocean currents and sea ice in the far north have changed through the Holocene. In a new study, published in the Journal of Geophysical Research: Oceans, scientists at the University of Oxford in England studied more than 900 pieces of driftwood collected from Arctic shorelines since the 1950s to investigate how shifting Arctic Ocean currents help melt or fortify sea ice.

Travels in Geology: Roaming the rocky coastline of Downeast Maine

Mon, 18 Dec 2017 09:28:31 -0500

Jordan Pond was formed by an ice sheet during the Wisconsinan glaciation. A flat path that loops around the pond offers views of North Bubble and South Bubble, the two rounded hillocks seen in the distance. Credit: Bethany Augliere.

Sitting atop the bald, pink granite ledges of Cadillac Mountain in Maine’s Acadia National Park, I watched the sunset from the highest point along the North Atlantic seaboard. The expansive view reveals a stunning landscape carved from glaciers, with elongated lakes and ponds and rounded mountaintops in the distance. As the sky darkened, the moon rose above the horizon and over the nearby harbor. From this vantage point, on winter mornings from Oct. 7 through March 6, you can also catch the first glimpse of sunrise in the United States.

Benchmarks: January 25, 1968: The last firefall: A Yosemite tradition flames out

Thu, 14 Dec 2017 18:32:56 -0500

The spectacle known as firefall — in which burning embers were pushed off Glacier Point in Yosemite National Park to create a flaming cascade — was a beloved tradition for nearly a century. Credit: public domain.

Fifty years ago this month, on Jan. 25, 1968, a massive bonfire built of red fir bark atop Glacier Point in Yosemite National Park was burned down to embers and, promptly at 9 p.m., and for the last time, pushed over the cliff edge to create a flaming cascade for the viewing enjoyment of tourists gathered below. The spectacle, called "firefall," had been a beloved Yosemite tradition for nearly a century.

Ice (Re)Cap: January 2018

Thu, 14 Dec 2017 18:14:45 -0500

Using data from the Dumont d'Urville research station on the coast of East Antarctica, researchers determined that dry katabatic winds over Antarctica substantially decrease the amount of snow that reaches the continent's icy surface. Credit: Environmental Remote Sensing Laboratory, Swiss Federal Institute of Technology (LTE/EPFL).

Western wildfires affect water quality

Thu, 14 Dec 2017 17:50:55 -0500

Wildfires are likely to increase sediment loads in watersheds across the U.S. West, according to new research. In this false-color image taken Oct. 21, 2017, by the Terra satellite, areas burned (dark gray) by recent wildfires in the vicinity of Santa Rosa and Napa, Calif., can be seen amid living vegetation (red). Credit: NASA/METI/AIST/Japan Space Systems, and U.S./Japan ASTER Science Team.

Wildfires have burned increasing acreage in recent decades, a trend that’s expected to continue with global climate change. In the U.S. West, the frequency of fires has implications for water availability — both water used to fight wildfires and municipal water supplies, which can be contaminated by loosened debris from eroding, fire-burned slopes.

Geologic Column: Celebrating Old Rock Day

Thu, 14 Dec 2017 17:05:31 -0500

Move over New Year’s: There’s a new favorite holiday in January, at least for geologists. Jan. 7 marks “Old Rock Day.” No, this is not the day to celebrate old rock ’n’ roll music or the elderly musicians still playing it. Old Rock Day is the day that geoscientists and rock enthusiasts encourage people to celebrate and learn more about old rocks and fossils.

Impact signature in rock produced by lightning strikes

Thu, 14 Dec 2017 15:47:34 -0500

A new study suggests that lighting strikes can create shock features on rocks that were previously thought to form only as a result of meteorite impacts. Credit: public domain.

When a meteorite smashes into Earth’s rocky surface, the immense temperatures and pressures created can melt rock into glass and leave signatures of the impact behind. Impacts produce tell-tale planar features in quartz grains called shock lamellae — picture a scrambled television signal, with repeating horizontal lines chopping and distorting the image into layers — that scientists have thought were produced only by meteorites.

In feats of tectonic strength, grain size matters

Thu, 14 Dec 2017 15:43:47 -0500

Olivine is the dominant mineral in Earth's lithosphere, and thus largely controls the strength of tectonic plates. Credit: Evan Krape/University of Delaware.

Plate tectonics involves some of the most powerful forces on Earth, but the lithosphere, of which the plates are made, is not infinitely strong: Weaknesses in the lithosphere allow it to break apart and form plate boundaries. Determining the strength of tectonic plates based on field observations has proved tricky, however, due to the sheer scale of plates, while experiments and calculations in the lab on olivine — the main mineral that makes up the lithosphere — have depicted plates as misleadingly strong. In a new lab-based study, researchers have taken a novel approach to testing olivine’s strength, and the results fit existing models of plate tectonics better than previous efforts.

From space to village: NASA's SERVIR program brings a big picture to local communities

Thu, 14 Dec 2017 14:43:49 -0500

Through its SERVIR program, NASA is putting geospatial satellite images and analysis tools into the hands of local decision-makers around the world to help them address natural disasters and the effects of climate change. Credit: K. Cantner, AGI (base image: ©iStockphoto.com/sushi7688).

Life is tightly linked to weather in the Lower Mekong countries of Southeast Asia, and the weather is rarely still. In 2016, the Mekong River was at its lowest level since 1926 as the region endured the second season of its worst drought in 90 years. The drought was felt across Cambodia, Laos, Myanmar, Thailand and Vietnam, jeopardizing exports like rice, seafood and fruit. In 2015, the Thailand Ministry of Agriculture and Cooperatives even asked rice farmers to delay their early summer planting because of water shortages, a move with big financial risks.

In the lab, machine learning improves quake forecasts

Thu, 14 Dec 2017 14:37:11 -0500

Researchers used machine learning to analyze acoustic signals (bottom signal) from a laboratory fault model subjected to shear stress (top signal) and found the early "groaning, creaking and chattering" emitted by the fault model helped predict when it would fail. Credit: Rouet-Leduc et al., Geophysical Research Letters, September 2017.

The U.S. Geological Survey estimates that about 500,000 detectable earthquakes occur worldwide every year. But accurate forecasts of when quakes will occur have long been out of reach, in large part because of the complexities of fault behavior.

Turkey DNA reveals Mesa Verde denizens moved to New Mexico

Thu, 14 Dec 2017 14:34:24 -0500

The Mesa Verde region of southern Colorado was home to as many as 30,000 Puebloans through the middle of the 13th century, until severe drought drove them south into New Mexico, ending the cliff dwellers’ reign. In a new study, researchers have charted this mass migration using mitochondrial DNA from a novel source: turkey bones from the domesticated birds kept by Puebloans in both Mesa Verde and northern New Mexico.

Nautical charts reveal coral decline around Florida Keys

Thu, 14 Dec 2017 14:31:40 -0500

Eighteenth-century British nautical charts — such as this one from 1774 (left), which shows the locations of coral reefs around Key West, Fla. — were compared to modern surveys of coral habitats in a new study. Credit: Loren McClenachan.

Coral reef cover is known to have decreased over the past few decades, but longer term estimates of coral cover have been difficult to reconstruct. In a new study, researchers used high-resolution historical nautical maps from the 18th century to determine changes to reefs in the Florida Keys.

Earthquakes shaped ancient Greek culture

Thu, 14 Dec 2017 07:06:10 -0500

Iain Stewart studies the remains of a fifth-century-B.C. temple built atop a fault-formed fissure at Ephesus in western Turkey. Credit: Stephen Vaughan.

In ancient Greece, earthquakes frequently shook the ground and devastated cities and temples. But time after time, people built — and rebuilt — prominent structures near dangerous faults. How much the ancient Greeks knew about earthquakes and fault behavior is unclear. But in a new study in Proceedings of the Geologists’ Association, researchers suggest that the relationship between sacred sanctuaries and faults is more than coincidental, and that earthquakes may have had a previously underappreciated cultural significance to the ancient civilization.

Volcanism spiked global temps during past hothouse

Thu, 14 Dec 2017 07:03:29 -0500

Kilometers-thick layers of volcanic rock that formed as the North Atlantic ocean basin opened between Greenland and Norway make for stunning mountain backdrops in eastern Greenland today. Carbon emissions that accompanied this volcanism may have caused the large-scale global warming of the Paleocene-Eocene Thermal Maximum. Credit: Michael Storey, Natural History Museum of Denmark.

Roughly 56 million years ago, global temperatures rose 5 degrees Celsius within a few thousand years in an event called the Paleocene-Eocene Thermal Maximum (PETM). Scientists have often attributed the relatively rapid warming of the PETM — frequently used as an analogue for understanding modern warming trends — to large-scale biogenic methane emissions from seafloor reservoirs. But in a new study, researchers tracking carbon and boron isotopes preserved in the shells of tiny marine creatures called foraminifera, or forams, question the conventional wisdom, instead pointing to a volcanic source for the carbon emitted during the PETM.

New Zealand quake triggers two large slow-slip events

Thu, 14 Dec 2017 07:00:37 -0500

The 2016 Kaikoura earthquake set off slow-slip events off the east coast of New Zealand's North Island as well as beneath the country's capital, Wellington. Credit: K. Cantner, AGI.

On Nov. 14, 2016, a magnitude-7.8 earthquake struck near Kaikoura on New Zealand’s South Island, setting off a cascade of fault ruptures in the region. Within hours, seismic waves from the quake triggered a two-week-long slow-slip event on a section of the Hikurangi Subduction Zone between 250 and 600 kilometers north of the initial epicenter, as well as ongoing slow slip on the Hikurangi beneath New Zealand’s capital, Wellington, according to a new study in Nature Geoscience. Thanks to New Zealand’s advanced seismic and tectonic monitoring networks, the event is one of the best-documented examples of an earthquake triggering slow slip on distant faults.

Geologic Column: Dams in distress

Mon, 11 Dec 2017 13:25:24 -0500

Oroville Dam and Lake Oroville reservoir from the air, within the Lake Oroville State Recreation Area, northern California. Credit: public domain.

Catastrophic dam failures make news. The worst in U.S. history, the Johnstown Flood of 1889 in Pennsylvania, killed more than 2,200 people and produced more than $450 million in damage (in present-day dollars). Just last February, a potential catastrophe — thankfully averted — engulfed national news as the Oroville Dam in Northern California threatened to breach. The threat alone forced almost 200,000 people to evacuate from areas downstream that would’ve been flooded had the dam broken. As the Oroville reservoir filled during record-breaking rains, attempts to lower water levels in the reservoir relied partly on a poorly maintained emergency spillway that eventually gave way, threatening to breach the whole dam. The episode highlighted persistent issues with dam maintenance.

Down to Earth With: Volcanologist Jess Phoenix

Mon, 11 Dec 2017 13:15:11 -0500

Jess Phoenix, a volcanologist and co-founder of Blueprint Earth — a nonprofit organization that brings scientists together with students to inventory ecosystems — is running for Congress in California's 25th District. Credit: Belle & Epic Photography.

Field geologists usually love camping, hiking and all things outdoors. Today, Jess Phoenix is no different, but she wasn’t always that way. As a child growing up in Colorado, she bucked traditional backpack-wearing pursuits. “I would take the horses on trail rides and that was probably the most outdoorsy thing that I did,” Phoenix says. Instead, she took after the athletic interests of her parents, both FBI agents, playing “every sport under the sun.”

Comment: Making the first (and last) geoscience class count

Mon, 11 Dec 2017 10:08:48 -0500

From the InTeGrate homepage (serc.carleton.edu/integrate), instructors can navigate to many earth science modules, from programs on water resources or coastal hazards to minerals or diversity. All are designed to bridge science and society. Credit: InTeGrate/Carleton College, Science Education Resource Center.

Imagine that no one had ever taught a general education geoscience course for college students, and that you were given the job of designing such a course from scratch. As you look around today, would your first reaction be, “We’re going to need to spend three or four weeks talking about rocks and minerals”? Or would you be more inclined to discuss the challenges of addressing how the natural processes that sustain the earth system as we know it today — and that support our global community — are changing before our eyes? Not to be glib about it, but while geoscience educators go about our routine of presenting basic facts and concepts, we may be missing an opportunity to engage our students in more compelling conversations involving our science.

Travels in Geology: The geological riches of Quebec's Gaspé Peninsula

Thu, 16 Nov 2017 14:13:35 -0500

A quintessential view of the Gaspé Peninsula in eastern Quebec. Credit: ©iStockphoto.com/krblokhin.

The geological and paleontological riches of Quebec’s Gaspé Peninsula have been known since 1844, when it was first explored by Sir William Edmond Logan, who is often called the father of Canadian geology. Since then, it has become a location of interest for both amateur and professional geologists looking to explore pristine rock formations and an abundance of fossils.

Geomedia: Gifts: Holiday Gift Guide

Wed, 15 Nov 2017 21:36:29 -0500

There’s never a shortage of geeky pop-culture merchandise and gift ideas available, but sometimes it’s hard to find clever items that are less “Guardians of the Galaxy” and more about the actual galaxy. If you have science lovers on your holiday shopping list, look no further than EARTH’s Holiday Gift Guide for ideas — from space soap to science board games — that are sure to surprise and delight.

Benchmarks: December 5, 1952: The Great Smog smothers London

Wed, 15 Nov 2017 21:14:50 -0500

A clear day versus a smoggy day in Beijing. Winter smog can be especially thick and visibility can be reduced to meters. Scientists have recently used smog in Beijing to better understand what happened in London in 1952. Credit: both: Peter Barwick, www.flickr.com/photos/barwick.

On Friday, Dec., 5, 1952, a blanket of thick, yellow smog settled over London, cloaking the city for five days straight. Smog wasn’t uncommon — Londoners called these days “pea-soupers,” based on the yellow-black color — and there were notable smog episodes from the Industrial Revolution (late 1700s) through the 1950s. But the haze of the city’s infamous “Great Smog” of 1952 long overstayed its visit. The lingering smog killed thousands, and its residual effects lasted for decades.

Comment: Arctic warming and midlatitude weather: Is there a connection?

Wed, 15 Nov 2017 15:16:52 -0500

An ice floe slides down the starboard side of the Coast Guard Cutter Healy. Credit: USGS.

Over the past couple of decades, the Arctic has warmed more strongly than the rest of the planet. A big question within the climate research community is whether Arctic amplification has the potential to influence — or may already be influencing — weather patterns in the middle latitudes. The short answer is: We don’t know for sure, but it’s quite likely, with the results being more persistent weather patterns at midlatitudes that can lead to extreme events.

Red Planet Roundup: December 2017

Wed, 15 Nov 2017 14:58:41 -0500

NASA scientists produced a new map of Mars' crustal thickness based on a combined analysis of gravity and topographic data. The work suggests that the planet's crust is less dense on average and that variations in thickness between thicker (red) and thinner (blue) portions of crust are smaller than previously thought. Credit: NASA/Goddard/UMBC/MIT/E. Mazarico.

With two rovers patrolling the surface of Mars, six spacecraft orbiting above it, and scientists here on Earth studying the Red Planet from afar, new findings are announced often. Here are a few of the latest updates.

What drives hot spots of sea-level rise?

Wed, 15 Nov 2017 14:40:28 -0500

Researchers first uncovered hints of a sea-level rise hot spot along Florida's coastline in 2011 in the Indian River Lagoon, pictured here. Credit: NASA.

As sea levels creep up around the world, scientists have observed hot spots where regional rates of sea-level rise greatly outpace the global average. But what drives the formation of these hot spots, and how long they last, have been mysteries. In a new study, scientists tracking sea levels along the Florida coast suggest that the combined effects of two naturally occurring climate processes, the El Niño-Southern Oscillation (ENSO) and the North Atlantic Oscillation (NAO), control sea-level hot spot formation along the U.S. East Coast.

Caldera clays may hold key to lithium independence

Wed, 15 Nov 2017 14:29:17 -0500

Oregon's Crater Lake was created when water filled the caldera created by an enormous eruption of Mount Mazama about 7,700 years ago. Clay deposits at the bottom of the lake may concentrate lithium, according to a new study. Credit: Mary Caperton Morton.

Most of the world’s lithium is mined in South America and Australia. New research suggests that the United States may have its own untapped lithium supplies in lake deposits in the calderas left behind by large volcanic eruptions. In the study, published in Nature Communications, researchers detail a new way to detect deposits of the silvery white metal in places such as Crater Lake in southern Oregon.

Antimony may have poisoned Pompeii's drinking water

Wed, 15 Nov 2017 14:00:13 -0500

Lead pipes were used in water distribution systems in ancient Roman cities. Credit: Larry, CC BY 2.0.

The ancient Romans may have had advanced water distribution systems, but the water pipes they used were highly toxic. Many Roman-era water pipes were lined with lead, leading some archaeologists to suspect a public health crisis among Romans that may have contributed to the empire’s eventual fall. But others point out that the high levels of calcium carbonate in the Romans’ water supply would have quickly coated the pipes with scale, limiting the exposure of drinking water to lead. However, a new study suggests lead wasn’t the only concern: A sample of pipe from Pompeii dating to A.D. 79 has shown that the Italian city’s drinking water may have also contained alarmingly high levels of antimony. Antimony is an acutely poisonous element, ingestion of which can lead to severe vomiting, diarrhea, dehydration and/or death from ailments such as kidney failure and cardiac arrhythmia.

Volcanic activity contributed to first of the "Big Five" mass extinctions

Wed, 15 Nov 2017 13:52:36 -0500

Researchers found mercury concentration spikes in Late Ordovician rock sampled from this site in Nevada's Monitor Range, indicating a possible role for large-scale volcanic activity in a mass extinction roughly 444 million years ago. Credit: David S. Jones

During the Ordovician, between about 488 million and 444 million years ago, plant life first emerged on land, while primitive fish and a variety of marine invertebrates flourished in the oceans. Toward the end of the period, however, a mass extinction — the first of the so-called “Big Five” Phanerozoic extinctions — wiped out roughly 60 percent of all marine invertebrate genera. In a recent study, researchers shed new light on a possible cause of the Late Ordovician extinction: volcanic activity.

Imaging Iceland's volcanic roots

Thu, 09 Nov 2017 15:28:10 -0500

Ultralow-velocity zones (ULVZ) are patches of molten rock at the core-mantle boundary in which passing seismic waves slow significantly. Such patches may fuel plumes of hot rock that rise through the mantle to feed some volcanic hot spots, such as those beneath Hawaii and Iceland. Credit: Kaiqing Yuan and Barbara Romanowicz; modified by K. Cantner, AGI.

Home to more than 30 active volcanoes, Iceland is one of the most vigorous volcanic settings on Earth. A new look at the core-mantle boundary thousands of kilometers below the island is offering one of the most complete pictures yet of how Iceland’s volcanoes are fueled.

Alaskan subduction zone mirrors Tohoku zone that unleashed tsunami

Thu, 09 Nov 2017 15:21:06 -0500

This diagram shows the generalized structure of the subduction zone off the Alaska Peninsula near the Shumagin Islands. A large normal fault cuts through the entire overriding North American Plate at a roughly 45-degree angle and connects to the megathrust fault along which the North American and Pacific plates move against each other. Credit: K. Cantner, AGI, based on data from Bécel et al., Nature Geoscience, 2017.

In 2011, a large swath of coastal Japan was devastated and more than 15,000 people were killed when the magnitude-9.1 Tohoku earthquake unleashed massive tsunami waves that inundated land with run-up heights of 30 meters in places. In a new study, researchers have discovered that the seafloor off the Alaska Peninsula exhibits structures and fault patterns similar to the region where the Tohoku quake originated — a finding that may indicate a higher tsunami risk for coastal Alaska than previously thought.

Marine megafaunal extinction discovered

Thu, 09 Nov 2017 15:07:39 -0500

Fossils from Pliocene megafauna: sharks' teeth from Carchahinus leucas (left) and Negaprion (right). Credit: University of Zurich.

Extinctions of large land animals during the Pleistocene are well documented. In a new study, scientists report that marine megafauna also suffered severe losses several million years ago, around the time that the first hominid ancestors were emerging in Africa.

Desktop seismology: How a maker-inspired device is changing seismic monitoring

Wed, 08 Nov 2017 12:37:49 -0500

Created in 2016, the Raspberry Shake is a personal seismograph that can detect local to regional earthquakes. The Shake was developed by OSOP, a geophysical instrument company headquartered in Panama. Marketed toward makers and the earthquake-curious, it also has the potential to help professionals increase the station density of seismic monitoring networks. Credit: OSOP.

Earth groans and shimmies constantly, producing everything from occasional building-collapsing earthquakes to subtle shaking humans don’t even feel. There are many ways to track this shaking, ranging from sensitive, expensive seismograph stations to various citizen-science approaches, including the U.S. Geological Survey’s “Did You Feel It?” program, through which people can report what they felt during an earthquake using an online survey.

Bare Earth Elements: Bone up on your spooky geo-vocabulary this Halloween

Tue, 31 Oct 2017 15:18:02 -0400

This list of Halloween geo-jargon is full of fire and brimstone. Or at least brimstone, which of course is just sulfur. Smelly, but not all that scary on its own. Credit: Nadj91, CC0

I simply couldn’t resist writing this post. While I’m hardly a fanatical Halloween guy, I am an impassioned lover of puns and word humor (typically, the more Dad-like, the better in my book). And so when it occurred to me I could crack open my big ol’ “Glossary of Geology” to scour it for some of the eerier sounding jargon within, it seemed a perfect way to acknowledge the day. Fear not … unlike with H.P. Lovecraft’s “Necronomicon,” there are no ancient or evil powers to be conjured from the netherworld by speaking these ghastly glossary entries. You might, however, summon an appreciation for the some of the fiendish creativity and ghoulish humor that’s gone into earth science’s vast lexicon.

Benchmarks: November 18, 1929: Turbidity currents snap trans-Atlantic cables

Fri, 27 Oct 2017 12:15:18 -0400

The first trans-Atlantic submarine cable was laid in 1858, from Newfoundland, Canada, to Ireland. Credit: public domain.

On the evening of Monday, Nov. 18, 1929, a magnitude-7.2 earthquake ruptured off the coast of Newfoundland, Canada. Those living on the Burin Peninsula, a foot of land that reaches into the Atlantic Ocean, reportedly felt five minutes of shaking — a confusing sensation, since no one in the area had experienced an earthquake before. “Suddenly this roar — this loud banging — [occurred] and the kettle and the plates started to dance,” Gus Etchegary, a resident of the Burin Peninsula who had experienced the quake, described in a documentary video produced by The Newfoundland and Labrador Heritage Website.

Geologic Column: Giving Konrad Zuse his due

Fri, 27 Oct 2017 12:02:16 -0400

Statue of Konrad Zuse, Bad Hersfeld, Germany. Credit: Profiler 1888, CC BY-SA 3.0.

German engineer Konrad Zuse is considered the first inventor of the programmable electronic computer in his home country, but sadly, few students elsewhere learn of his pioneering efforts. Zuse’s legacy extends beyond his groundbreaking circuit designs, also encompassing advances in computational theory and even philosophical musings about the computational nature of the universe.

Getting there and getting around Scotland's Southwestern Islands

Thu, 26 Oct 2017 21:08:16 -0400

The Caledonian MacBrayne (CalMac) ferry service is the primary way to access Arran and Islay from mainland Scotland. Credit: James Stringer, CC BY-NC 2.0.

Ferry service to Arran and Islay is the primary way to access the islands from the Scottish mainland. Caledonian MacBrayne (“CalMac”) offers a “hopscotch” ticket package that goes from Ardrossan (close to Glasgow) to Brodick (Arran), across the Kintyre Peninsula, to Port Ellen (Islay), and then back to Kintyre, all on your own schedule, for £150, including ferrying your rental car. (We brought a rental car with us from the mainland, in the interest of being able to access outcrops where and when we wanted, but each island offers a municipal bus service as well.) Reserve a space for your car on the ferry during peak tourist times. Also, be prepared to be stuck on an island for a bit (usually not more than a few hours) if the weather turns.

Travels in Geology: The diverse geology, landscapes and whiskys of Scotland's Southwestern Islands

Thu, 26 Oct 2017 20:41:54 -0400

Goatfell is the highest point on the Isle of Arran. The granitic mountain is also a showpiece of alpine glaciation. Credit: ©iStockphoto.com/mille19.

Arran and Islay are two large islands of southwestern Scotland that showcase a suite of interesting rocks and landscapes, and Scotland’s second-finest product (after the geology): single malt whisky. Visiting Arran and Islay together is an enjoyable experience in contrasts. Both islands are sparsely populated, with a few thousand permanent residents each, but amenable to tourists, boasting well-developed infrastructure, including regular ferry service from the mainland. Arran is mountainous, while Islay has relatively subdued topography. Both get a lot of visitors in the summer and feature a wealth of cultural and recreational opportunities, in addition to outcrops that will prove insightful to the geologically minded traveler.

Comment: The Congressional ecosystem: A paleontologist's perspective

Wed, 18 Oct 2017 14:17:59 -0400

Credit: Callan Bentley, 2017.

At the height of the 2016 presidential election, the nation’s eyes were on Washington, D.C., and prominent voices were critical of the Capital. “Washington is full of fossils” and “the swamp is rotten” were common refrains all along the political spectrum. Who better to head to Congress than a paleontologist with a specialty in soft-tissue preservation? I spent years dealing with fossils and rot. I was prepared for anything — or so I thought.

Down to Earth With: Deep-sea biologist Stace Beaulieu

Wed, 18 Oct 2017 14:10:58 -0400

Stace Beaulieu is a senior research specialist at Woods Hole Oceanographic Institution (WHOI) in Woods Hole, Mass., who studies the biology of deep-sea ecosystems, including hydrothermal vents. Credit: Tom Kleindinst, WHOI.

People often find their way to the geosciences after a college class sparks their interest. But not Stace Beaulieu, a senior research specialist at Woods Hole Oceanographic Institution (WHOI) in Woods Hole, Mass. — she knew what she wanted to do at age 6. Beaulieu grew up in Florida and spent her childhood snorkeling and reading science magazines with pictures of deep-sea creatures that tantalized her imagination and piqued her curiosity. “I had a one-track mind pretty much from elementary school through grad school — I never changed my mind. I was so excited about learning about what was deeper. I still am today.”

Ice (Re)Cap: November 2017

Wed, 18 Oct 2017 12:21:26 -0400

Jarvis Glacier flows from Mount Silvertip in the eastern Alaska Range. Runoff from mountain glaciers supplies water to streams and recharges aquifers in Alaskan watersheds. Credit: Anna Liljedahl.

Microbes influence ooid formation

Wed, 18 Oct 2017 12:17:43 -0400

A thin section of ooids showing their concentric carbonate coatings. Credit: Strekeisen, CC BY-SA 4.0.

The formation of carbonate spheroids called ooids is a bit of a mystery. They are thought to form in warm waters saturated with carbonate, which combines with calcium to form concentric layers of calcium carbonate on shell fragments or sand grains. Some scientists have suggested that the presence of microbes might encourage calcium carbonate to precipitate out of water to form ooids in a process called organomineralization.

Northern Finns didn't starve during Little Ice Age

Fri, 13 Oct 2017 14:01:29 -0400

Today, Finland’s Northern Ostrobothnia region is one of the northernmost places in Europe that can support agriculture. But how this region fared during the Little Ice Age — a period of globally cooler temperatures that lasted roughly from A.D. 1300 to 1850 — is unknown. Scientists assume the climatic cooling would have adversely affected food supplies. Now, however, the discovery of a mysterious medieval cemetery in northern Finland dating to the middle of the Little Ice Age is offering clues that the inhabitants were well fed and well suited to the northern clime.

Can distant earthquakes trigger submarine landslides?

Fri, 13 Oct 2017 13:58:45 -0400

Underwater landslides, called turbidity currents, occur when material on seafloor slopes destabilizes and flows downhill. In a new study, researchers suggest that shaking from a major earthquake in the Indian Ocean caused turbidity currents 13,500 kilometers away on the Cascadia Subduction Zone. Credit: K. Cantner, AGI.

Large earthquakes can nudge both nearby and distant faults closer to failure, sometimes setting off additional earthquakes halfway around the world. New evidence from the Cascadia Subduction Zone suggests that large seismic events can also trigger submarine landslides, called turbidity currents, perhaps as far as 13,500 kilometers away. If true, researchers say such long-distance connections could complicate interpretations of paleoseismic records from the Cascadia margin and elsewhere that rely on data from turbidites — the stratified remains of the underwater slides — to piece together when past local earthquakes occurred. But not everyone is convinced that long-distance landslide triggering is possible.

How long will the lava flow? Predicting eruption durations with satellite monitoring

Fri, 13 Oct 2017 13:55:49 -0400

This false-color image of the 2014 Holuhraun eruption and lava field in Iceland was captured by the Landsat 8 satellite. Credit: NASA Earth Observatory/Jesse Allen.

If you live near a lava-spewing volcano, it could be helpful to know just how long molten rock might flow during a fiery eruption. In a new study, scientists report that they can calculate how long lava-flowing eruptions might last based on satellite data.

Mangroves sprouted in Arctic during Eocene

Fri, 13 Oct 2017 13:51:03 -0400

Evidence of ancient mangrove plants was found in lignite seams, such as in this outcrop on Faddeevsky Island. Credit: Guillaume Suan.

Mangrove trees, which today thrive in tropical and subtropical climates in the low and midlatitudes, grew in the high Russian Arctic about 56 million years ago, scientists reported in Geology. It’s the northernmost occurrence of mangrove trees ever documented.

Microbes care about energy efficiency

Fri, 13 Oct 2017 13:48:20 -0400

Researchers found that archaea collected from this hot spring in Yellowstone National Park chose unexpectedly when offered a variety of food sources. Credit: Maximiliano Amenabar.

Microbes live in some of the most extreme environments on Earth, from the crushing depths of deep-sea trenches to scalding geothermal springs. Part of the reason microbes thrive in many different environments is their ability to use a variety of energy sources — including light, organic matter, and inorganic materials like hydrogen, sulfur, and iron — to power the metabolic reactions that allow them to grow and survive.

Pharmaceuticals in urban sediments reveal wastewater treatment effectiveness

Fri, 13 Oct 2017 09:57:47 -0400

Scientists collected sediment samples from a dammed pond on the Loiret River in Orléans, France, to investigate the accumulation of pharmaceutical products downstream of wastewater treatment plants. Credit: ASRL.

People take pills to relieve headaches or syrups to ease a hacking cough, and eventually these medications can make their way into streams and rivers around the world as humans excrete the chemicals. Scientists are now using concentrations of common pharmaceutical products (PPs) in river sediments in Orléans, France, to determine how effective four water treatment plants have been at removing chemicals from the environment.

Limestone reservoirs boost volcanic carbon emissions

Fri, 13 Oct 2017 09:44:40 -0400

New research suggests that arc volcanoes, which release large amounts of carbon when they erupt, draw their carbon from limestone platforms found along subduction zones. Credit: K. Cantner, AGI.

Volcanoes have been the main source of atmospheric carbon over Earth’s history, with some types of eruptions injecting more carbon into the atmosphere than others. Arc volcanoes, for example, which form in chains along subduction zones, are responsible for up to two-thirds of all volcanic carbon emissions today, and have likely been major contributors for as long as they’ve existed. New research suggests a reason why: These volcanoes draw large amounts of carbon from limestone platforms found along many subduction zones. The finding has implications for how the volcanic carbon cycle affects climate over geologic timescales.

New method offers improved monitoring of Kilauea

Tue, 03 Oct 2017 15:33:28 -0400

Steam rises from Kilauea's Halema'uma'u Caldera. Credit: Nathan Forget, CC BY 2.0

Kilauea Volcano, on Hawaii’s Big Island, has been erupting continuously since 1983, mostly releasing relatively slow-moving lava flows, although rare violent eruptions have occurred. Both explosive and nonexplosive eruptions pose risks to tourists, roughly 2.6 million of whom visit Kilauea annually, as well as to island residents whose safety and property have at times been put in jeopardy by flowing lava.

Down to Earth With: Alexander Stewart

Wed, 20 Sep 2017 13:32:05 -0400

Alexander Stewart. Credit: Alexander Stewart.

Sgt. Alexander Stewart was brought up to believe serving in the military was an obligation all young men should fulfill. In 1991, at the age of 17, he answered the call of duty and joined the U.S. Army, which took him to Alaska with the 6th Infantry Division (Arctic)(Light). The state’s endless snow and ice fascinated Stewart, and after he left active duty, he pursued a bachelor’s degree in geology. In 2007, he completed a doctorate at the University of Cincinnati — in glacial geology, of course. Now he teaches the subject at St. Lawrence University in New York.

Geologic Column: A masochist hikes through the heather

Tue, 19 Sep 2017 11:49:12 -0400

A hike through the Scottish Highlands could be a delightful sojourn or a masochistic, miserable plod through rain. Credit: Alex Berger, CC BY-NC 2.0.

Callan Bentley’s delightful article on the Scottish Highlands in the May 2017 EARTH took me back to my first encounter with the Moor of Rannoch and the Pass of Glencoe in the Grampian Highlands, about 80 kilometers south of the part of Scotland that Bentley describes. According to “Monty Python and the Holy Grail,” it’s where the Bridge of Death and the Gorge of Eternal Peril are. And in 1960, cartoonist Carl Barks revealed that the Hound of the Whiskervilles might be found prowling the vicinity of Castle McDuck, ancestral home of Disney’s Donald on Rannoch Moor.

Water weight and surface rebound trigger small quakes in California

Tue, 19 Sep 2017 11:43:11 -0400

California's record-setting snowpack this year may affect stress on faults throughout the state. In May 2017, only the roof of this two-story cabin in the Sierras was visible above the snow. Credit: Mary Caperton Morton.

On average, a cubic meter of snow weighs less than 100 kilograms, but heavy, compacted snow can weigh more than 500 kilograms per cubic meter, with glacial ice approaching 900 kilograms per cubic meter. In California, as elsewhere, the weight of winter snow and spring runoff pushes down on the landscape, affecting stresses on fault systems, which may trigger small quakes. As the snow melts and the runoff makes its way downstream, land rebounds, setting off more small earthquakes.

First complete DNA sequences from Egyptian mummies

Tue, 19 Sep 2017 11:40:48 -0400

Egypt's hot and humid conditions may not be as detrimental to ancient DNA as thought. Credit: British Museum, CC BY-NC-SA 4.0.

Egyptian mummies provide archaeologists with a tantalizing window into ancient Egyptian culture. And now they are offering up their DNA.

Mapping Louisiana's disappearing shoreline

Tue, 19 Sep 2017 11:38:19 -0400

A new map of subsidence rates is helping scientists and policymakers chart land loss along the Louisiana coast. Credit: Nienhuis et al., GSA Today, June 2017.

Since the 1930s, Louisiana has lost an area of coastal wetlands larger than the state of Delaware. A new map, published in GSA Today, charts the land loss from a combination of man-made and natural factors, including reduced sediment flow from the Mississippi River, land subsidence and sea-level rise.

Lollipop-shaped ice found in clouds

Tue, 19 Sep 2017 11:35:26 -0400

Researchers recently found tiny lollipop-shaped ice crystals over the Atlantic Ocean. Credit: Callan Bentley, 2017.

A sky full of lollipops might sound like a candy-filled dream, but these “treats” aren’t what you might think.

Solar-powered paint could produce hydrogen for fuel

Tue, 19 Sep 2017 11:33:12 -0400

Newly developed solar paint adsorbs moisture from humid air at night and splits the water molecules into oxygen and hydrogen during the day. Credit: RMIT University.

Split a water molecule, and you get hydrogen and oxygen. Burn that hydrogen as fuel and you get water. This straightforward, pollution-free cycle is part of what makes hydrogen so tantalizing as a potential renewable fuel. Unfortunately, splitting water molecules to generate hydrogen is not currently very energy efficient. In fact, more than 95 percent of hydrogen currently used in industry is produced from fossil fuels, not water.

Minerals deformed by meteorites reveal age of impact

Tue, 19 Sep 2017 11:30:41 -0400

The Willamette Meteorite on display at the American Museum of Natural History in New York City. Credit: Dante Alighieri, CC BY-SA 3.0.

Researchers have discovered a new way to determine when a meteorite hit Earth, a technique that could not only help scientists date ancient meteorite strikes but also determine when planetary crusts first formed.

Geomedia: Radio: "Big Picture Science" aptly named

Mon, 18 Sep 2017 14:41:31 -0400

The weekly "Big Picture Science" radio show crew (from left to right) includes Co-Host Seth Shostak, former intern Jay Weiler, Operations Manager Barbara Vance, Producer Gary Niederhoff, and Co-Host Molly Bentley. Credit: Big Picture Science/SETI.

Titles can sometimes be a hard thing to live up to, but “Big Picture Science,” a weekly radio program broadcast on about 100 stations nationwide, delivers on its name. The show, which cleverly covers everything from a study of frogs in pants to efforts to create a compassionate computer, lives up to its mission of presenting a wide-angle view of science and technology.

Travels in Geology: Cones and craters in Flagstaff, Arizona

Mon, 18 Sep 2017 13:20:03 -0400

Although better known for its parched deserts and graceful saguaros, Arizona also hosts a wide variety of spectacular volcanic features, including Grand Falls. This waterfall, which only flows at certain times of the year when snows melt or monsoon rains fall, was created when a lava flow from Merriam Crater blocked the channel of the Little Colorado River. Credit: Terri Cook and Lon Abbott.

When it comes to U.S. volcanoes, most people think of Hawaii, Alaska, or Mount St. Helens and Mount Rainier in the Pacific Northwest. Ask them about Arizona, and images of the Grand Canyon, red rock deserts and saguaros baking in the sun probably come to mind. But Arizona also hosts an impressive volcanic field. Near the outdoorsy college town of Flagstaff in northern Arizona, more than 600 mounds and mountains — every one of them a volcano in the San Francisco Volcanic Field — are sprinkled across the high plateau on which the town is perched. Few places in the country exhibit so many types of volcanic features, including jagged lava flows, crumbly cinder cones and the remnants of a towering stratovolcano, in such a compact region. This great diversity led NASA to select the area as a training ground for the Apollo astronauts in the 1960s and ‘70s. But Flagstaff’s cones and craters, and the region’s spectacular scenery, also offer non-astronauts an out-of-this-world experience.

New map of Arctic geology published

Thu, 14 Sep 2017 12:54:40 -0400

A new map of Arctic resources highlights diamond and metal deposits. Credit: Geological Survey of Norway.

At first glance, it might seem there’s little more to the Arctic than frozen tundra, ice and seawater, but the top of the world is home to some unique geology and an impressive array of mineral resources. A new project led by the Geological Survey of Norway (GSN) has compiled all existing geologic data about the Circum-Arctic region into a book, database and interactive map.

How the Arctic became salty

Thu, 14 Sep 2017 12:48:13 -0400

During the Eocene, the Arctic Ocean was a giant freshwater lake fed by rivers and ice melt. Today, it's salty and ice-covered much of the year. Credit: NASA.

The Arctic Ocean hasn’t always been as salty as other oceans. In the Eocene, between 56 million and 34 million years ago, the water surrounding the North Pole — freshened by melt from sea ice and river runoff — was cut off from the Atlantic and Pacific oceans by land bridges. At some point, plate tectonic processes opened the North Atlantic, submerging the land bridges and allowing saltwater to pour into the Arctic, but the timing and details of these events are largely unknown. New research suggests a tipping point may have been reached as one particular land bridge submerged far enough below the ocean surface.

Comment: The Anthropocene: Foregone or premature conclusion? Examining the ethical implications of naming a new epoch

Thu, 14 Sep 2017 12:15:59 -0400

Credit: Kevin Walsh, CC BY 2.0.

The scientific movement to declare a new geological epoch called the Anthropocene has received a lot of attention in the popular press. There seems to be an impression that designating an Anthropocene Epoch is a cool or compelling way to recognize that human societies have caused recent and ongoing global climate change, as well as other systemwide impacts on Earth, including acidification of the oceans, widespread species endangerment and landscape changes. I have even heard it said that the idea of the Anthropocene is a way to acknowledge and begin facing our personal and collective responsibilities with respect to those impacts.

Comment: Providing resources for future generations - Technical and human challenges

Thu, 14 Sep 2017 12:06:06 -0400

Credit: RFG 2018.

Earth is a remarkable planet, providing us with a comfortable place to live and the energy, minerals and water to sustain our societies. Geoscientists understand the dynamic processes within, and at the surface of, our rocky planet that shape our unique home. Plate tectonics and related processes have operated throughout much of Earth’s history, leading to repeated amalgamation and breakup of supercontinents; the building and erosion of mountain ranges thousands of kilometers long; the constant delivery of massive quantities of sediment from the continents into adjacent sedimentary basins; and disruptive and hazardous events such as earthquakes, volcanic eruptions and violent storms. These and other geological processes have moved and concentrated metals, minerals, hydrocarbons and water. The resulting concentrations of natural resources were so obvious that ancient humans recognized and exploited them beginning more than 10,000 years ago.

Glass shards reveal a fiery history in Ethiopia

Thu, 14 Sep 2017 11:51:18 -0400

Scientists drilled below Lake Ashenge, on the western border of the Afar Triangle, for evidence of past eruptions. Credit: Catherine Martin-Jones.

Chains of volcanoes and a lava lake pepper the landscape of the Afar Triangle in northeastern Ethiopia, where eruptions and earthquakes are byproducts of the rifting that is literally ripping Africa apart, but recent eruptions have been docile. Now, scientists studying ash deposits from the last 40,000 years are showing that dangerous, explosive eruptions present an ongoing hazard, striking the region every 1,000 years on average.

Volcanism triggered end-Triassic extinction

Thu, 14 Sep 2017 11:47:17 -0400

These continental sedimentary layers in Morocco spanning the end-Triassic mass extinction event were analyzed for mercury content in a new study. Credit: Jessica Whiteside.

The end-Triassic mass extinction exterminated up to three-quarters of all species on land and in the oceans 201 million years ago. This die-off opened up ecological niches and allowed for, among other changes, dinosaurs to diversify and spread across terrestrial ecosystems during the rest of the Mesozoic. Volcanism has long been implicated in the extinction, but whether it had a major impact on the planet at the time has remained unclear. In new research, scientists observed elevated mercury concentrations in extinction-aged rocks from around the world. Because volcanism is the main nonanthropogenic source of mercury in the environment, the findings suggest that volcanic activity was likely the main extinction trigger at the end of the Triassic.

Jerusalem tower facelift reveals it's 1,000 years younger

Thu, 14 Sep 2017 11:44:20 -0400

The base of the Spring Tower built to protect Jerusalem's Gihon Spring is 7 meters thick, constructed from boulders and sediment. Credit: Weizmann Institute of Science.

Jerusalem is one of the oldest cities in the world, dating back to at least 2400 B.C. Downhill from the heart of the city is Gihon Spring, a year-round natural fount that was likely the primary water source for the ancient city. Defensive fortifications built around the spring, known as the Spring Tower, were originally dated to the Middle Bronze Age, around 1700 B.C., but a new study reveals the tower could be as much as 1,000 years younger.

Down to Earth With: Evan Thomas

Fri, 01 Sep 2017 14:37:31 -0400

At age 16, Evan Thomas made a list of 100 life goals — his bucket list. At only 27 years old, he's done pretty well so far: Graduate college with a degree in aerospace engineering — check. Get a doctorate by age 25 — almost (missed by 11 days). Work for NASA — check. Start a business, help people, travel the world — check, check, check. Get a private pilot license — check. Climb the world's tallest mountains — in process. Credit: Courtesy of Evan Thomas.

At age 16, Evan Thomas made a list of 100 life goals — his bucket list. At only 27 years old, he’s done pretty well so far: Graduate college with a degree in aerospace engineering — check. Get a doctorate by age 25 — almost (missed by 11 days). Work for NASA — check. Start a business, help people, travel the world — check, check, check. Get a private pilot license — check. Climb the world’s tallest mountains — in process.

Down To Earth With: John Underhill

Fri, 25 Aug 2017 14:54:26 -0400

John Underhill. Credit: Courtesy of John Underhill.

“The Odyssey” follows Odysseus’ 10-year journey home to Ithaca after the Trojan War. John Underhill, a stratigrapher at the University of Edinburgh in Scotland, has been on his own odyssey over the past seven years — to test whether Ithaca actually existed. For centuries, scholars assumed that the people and places described by Homer in his epic poems were fictional, but archaeological finds elsewhere, such as Troy and Mycenae, have proven that these stories were grounded in reality.

Getting there and getting around Patagonia

Tue, 22 Aug 2017 15:22:02 -0400

Credit: Bottom: NASA/AGI.

There are many ways to get to Patagonia. I would have preferred to get there by following Charles Darwin’s route, aboard a replica of H.M.S. Beagle (especially considering that last year was the 200th anniversary of his birth). Sadly, the modern school calendar dictated that I move more quickly: Two weeks was all I had to work with.

Venturing into Argentina

Tue, 22 Aug 2017 15:12:58 -0400

Crucified lamb is a delicacy in Patagonian Argentina. Credit: Callan Bentley.

We chose to spend most of our time on the Chilean side of Patagonia, although you could just as easily decide to spend your entire trip on the Argentine side. But if you follow an itinerary similar to ours (see main story), it’s still worth a jaunt into Argentina. The town of El Calafate, an inexpensive five-hour bus ride from Puerto Natales, Chile, is a great place to sample wines from the Mendoza region and try the local delicacy, crucified lamb. The sheep is affixed to a steel cross and roasted slowly over a campfire. The resulting image is graphic, but the meat is tender and savory. El Calafate is also the gateway to Glaciers National Park. This park is home to many wondrous sights, but prime among them is the Perito Moreno Glacier, Argentina’s top tourist attraction.

Travels in Geology: Patagonia: The ends of the earth

Tue, 22 Aug 2017 14:52:16 -0400

The terminus of Grey Glacier in Torres del Paine National Park calves glaciers that accumulate downstream. Credit: Callan Bentley.

Certain place names conjure up a sense of remoteness that verges on the mythical: Timbuktu, Outer Mongolia, the Yukon. For me, prime among these legendary areas is Patagonia, a region of South America that encompasses much of the southern half of Argentina and Chile. But the exact borders are fuzzy: Where Patagonia starts and ends may lie more in the mindset of the traveler than in any physical landmark. You’ll know it when you get there.

Ancient wildfires suggest rising atmospheric oxygen helped end past ocean anoxia

Thu, 17 Aug 2017 17:15:07 -0400

Rising atmospheric oxygen levels may have spurred wildfire activity and helped bring an end to a bout of ocean anoxia about 180 million years ago. Credit: Chuck Hanlon, South Florida Water Management District, CC BY 2.0

Many times throughout Earth’s history, oxygen levels in the world’s oceans have decreased dramatically in episodes called oceanic anoxic events (OAEs), which have caused massive marine die-offs. In the Early Jurassic, for example, the Toarcian OAE has been linked with the extinction of many ammonite species and other sea life. However, how such episodes end remains largely unclear to scientists.

Getting there and getting around Bolivia's Antiplano

Wed, 16 Aug 2017 12:30:59 -0400

Traveling to Lake Titicaca and other parts of Bolivia can be quite an adventure. Credit: Terri Cook and Lon Abbott.

“Bolivia’s main gateway, El Alto International Airport (LPB), is located 13 kilometers southwest of the country’s capital, La Paz. It hosts regular, year-round flights to and from major destinations in South America, including Lima and Cuzco, Peru, Santiago, Chile, and Buenos Aires, Argentina, as well as connecting flights to Miami on American Airlines and Los Angeles, Washington, D.C. (Dulles) and Orlando, Fla., on Avianca. Several regional airlines, including Boliviana de Aviación (BoA) and Amaszonas, offer multiple flights daily from La Paz to Uyuni. The hour-long flight typically costs about $150 one way. We found the South American carriers to be extremely efficient; it’s important to arrive at the airport two hours in advance because the flights often depart early!

Travels in Geology: Sky-high adventure on Bolivia's Altiplano

Wed, 16 Aug 2017 12:20:27 -0400

Green Lagoon (Laguna Verde) is a highly concentrated salt lake located in the southwest of the Eduardo Avaroa Andean Fauna National Reserve at the foot of the Licancabur Volcano, Sur Lipez Province, Bolivia. The green-turquoise color of the water is due to suspension of arsenic and other minerals. Credit: ©iStockphoto.com/thomaslusth.

Nestled between two ranges of the rugged Andes Mountains, the Altiplano is a vast, windswept plateau that stretches more than 900 kilometers from southern Peru to northern Argentina. Most of this arid upland, which averages about 3,750 meters in elevation, sits in western Bolivia, where its surface is dotted with a series of stunning natural attractions. From the snow-white crystals of the world’s largest salt flats and flocks of pink flamingos in a brick-red lake to the startlingly azure waters of Lake Titicaca, the planet’s highest navigable lake, the Altiplano offers spectacular, vividly colored vistas for intrepid travelers. You could easily spend a month exploring this region, or get a tantalizing, week-long taste as part of a bigger South American journey, as we did in 2016, when we started in Peru and ended in Patagonia.

Geologic Column: Musings on the autumn equinox

Wed, 16 Aug 2017 11:35:21 -0400

Panaoramic color photograph made at Fredonian Nature Center in Shirley, Massachusetts, at the fall equinox, September 22, 2002. Credit: Bob Burkhardt, CC BY 3.0

Last month, many of us in the U.S. celebrated a relatively rare event — a full solar eclipse. That event, and the fact that the metal roof of my ranch house in California’s Santa Ynez Valley has started resonating with the thunk of raining acorns, got me thinking about our annual trip around the sun and the impending fall equinox.

Comment: A pitch to study BREW: The beer-renewable energy-water nexus

Wed, 16 Aug 2017 11:31:36 -0400

K. Cantner, AGI

Over the past few years, the food-energy-water nexus has become trendy for multidisciplinary systems-level research as it ties together three of the most critical elements of a modern society. Food security, energy security and water security are all inextricably linked, and the demand for all three is increasing. In recent years, the U.S. National Science Foundation has set aside $72 million to support research that spans these three topics. While I applaud this research path, I would like to suggest another topic that also warrants dedication from researchers: the beer-renewable energy-water nexus, or BREW. And I would further like to be the first to volunteer to personally collect field data at pubs and breweries nationwide.

Down to Earth With: Paleontologist Lisa D. White

Wed, 16 Aug 2017 11:19:12 -0400

Lisa White, assistant director of Education and Public Programs at the University of California Museum of Paleontology, at the 2016 meeting of the Society of Vertebrate Paleontology. Credit: Thea Boodhoo.

As a college student at San Francisco State University, Lisa D. White’s first choice of major was photography. She was drawn to landscapes, and dreamed of becoming “the black female Ansel Adams,” she tells me, surrounded by fossils. We’re in a lab at the University of California Museum of Paleontology (UCMP) in Berkeley, where she is assistant director of Education and Public Programs. She is also a micropaleontologist, and from 1990 until joining UCMP in 2012, she was professor of geology and later associate dean at San Francisco State University.

Benchmarks: September 23, 1806: Lewis and Clark's Corps of Discovery returns from the West

Tue, 15 Aug 2017 15:14:49 -0400

Captains Meriwether Lewis and William Clark, who, from 1804 to 1806, led the expedition of the Corps of Discovery to explore the United States' newly acquired territory. Credit: both: public domain.

It’s been called the greatest camping trip of all time. Statues, counties, waterways, mountains, military vessels, and even two colleges bear the names of the journey’s leaders. Their journals are among our greatest national treasures, and their adventures have inspired generations of explorers. Two hundred and eleven years ago this month, Captains Meriwether Lewis and William Clark and their 31-man Corps of Discovery returned to St. Louis, the frontier town where they had started their journey 28 months and nearly 13,000 kilometers of wilderness earlier on May 14, 1804.

Ice (Re)Cap: September 2017

Tue, 15 Aug 2017 14:33:37 -0400

River icings, like this 5-meter-thick one on the Echooka River in Alaska in 1972, are large masses of ice that form each winter in and around rivers across the Arctic. New research suggests river icings in Alaska and Canada are melting earlier in the year. Credit: U.S. Geological Survey.

Dehydrated sediment layer made Sumatra quake stronger

Tue, 15 Aug 2017 14:25:42 -0400

Map showing the rupture zone of the magnitude-9.1 Sumatra quake in December 2004, as well as the tsunami inundation zone and locations where scientists pulled up sediment cores that are adding to the understanding of the massive quake. Credit: K. Cantner, AGI.

Subduction zones are notorious for unleashing great earthquakes and tsunamis, such as the 2004 magnitude-9.1 Sumatra quake that caused shaking and inundations that killed more than 250,000 people and left millions more homeless. However, despite the dangerous reputations of subduction zones, their hazards are still often underestimated. New research reveals how sediments in the Sumatra Trench may have contributed to producing an even bigger earthquake and tsunami than hazard forecasts had estimated.

Reconstructing ancient oxidant levels and their climatic effects

Tue, 15 Aug 2017 14:23:14 -0400

Credit: Sara E. Pratt.

Oxidants in the troposphere, such as ozone and hydroxyl radicals, influence the life spans of other atmospheric components, including pollutants and greenhouse gases like carbon monoxide and methane. But how the abundance of tropospheric oxidants varies as climate changes is poorly understood. Part of the challenge is that these oxidants are too reactive to be preserved in paleo-records, such as ice cores.

Coatings may prevent pipeline clogs

Fri, 11 Aug 2017 14:01:14 -0400

Clogs caused by the formation of gas hydrates are a major concern for oil and gas pipeline operators. Water-repellent films coating the inside of pipes could prevent hydrate formation. Credit: Luca Galuzzi, CC BY-SA 2.5.

When ice forms in household water pipes, blockages and expansion can cause the pipes to burst. Similar problems can arise in the transportation of oil and gas when ice-like substances called gas hydrates build up inside pipelines — an issue traditionally mitigated by insulating pipes or by using antifreeze additives. But in a new study published in the journal ACS Applied Materials and Interfaces, researchers report an alternative solution: specialized coatings for the inside of oil and gas pipes that prevent hydrate buildups and clogs. The coatings could prove more reliable than the usual approaches, but whether the method can be applied cost-effectively on a large scale is uncertain.

A mammoth king: Was the legend of King Hygelac in "Beowulf" inspired by a fossil find?

Thu, 10 Aug 2017 14:35:44 -0400

Could woolly mammoth remains, found in the area where legend suggests King Hygelac and his Viking raiders were buried, have been misidentified as human bones in the eighth century? Credit: Hans Wildschut, courtesy of North Sea Fossils.

As far-fetched as it may seem, the death of a woolly mammoth thousands of years ago on an island in the Rhine-Meuse River Delta, near present-day Rotterdam in the Netherlands, could have led, millennia later, to the monsters and characters of “Beowulf.” The road from pachyderm to poem has many twists and turns, and following it calls for some literary and scientific sleuthing.

Earthquakes make volcanoes more — and less — gassy

Thu, 10 Aug 2017 11:30:57 -0400

Turrialba Volcano in Costa Rica showed an increase in sulfur dioxide emissions after earthquakes. Credit: ©iStockphoto.com/piratedub.

Triggering of volcanic emissions by earthquakes has been observed since antiquity. The Roman naturalist and philosopher Pliny the Elder proposed the link as early as A.D. 77, and in “The Voyage of the Beagle,” Charles Darwin wrote about inland eruptions in Chile closely following an offshore earthquake in 1835. More recent statistical studies show that after large earthquakes, volcanic activity around the world increases. But the lack of robust monitoring equipment at most volcanoes has made it hard to quantify the relationship. In a new study, scientists demonstrate how satellites can be used to track changes in sulfur dioxide emissions from volcanoes after seismic events, offering a potential way to study the often elusive link between seismicity and volcanism.

Transylvanian ice cave reveals European winter climate record

Thu, 10 Aug 2017 11:28:17 -0400

Over the last 10,000 years, water dripping into a cave in Transylvania has frozen into one of the largest and oldest cave glaciers in the world. Today, the Scărișoara Ice Cave in central Romania preserves one of the longest ice records on Earth, a boon for climate researchers seeking to study how Europe’s climate has fluctuated during the Holocene.

Young Costa Rican lavas might reflect pockets of primordial mantle

Thu, 10 Aug 2017 11:18:53 -0400

Komatiites are commonly found in Archean deposits, but a much younger flow found in Costa Rica may unlock some secrets about Earth's mantle. Credit: Esteban Gazel.

During the Archean, between 4 billion and 2.5 billion years ago, Earth’s super-heated young mantle produced a unique type of lava known as komatiite. In a new study published in Nature Geoscience, researchers looking at 90-million-year-old komatiites in Costa Rica — by far the youngest komatiites ever found — suggest the modern mantle may still harbor pockets of intense heat reminiscent of early Earth.

Geologic Column: Alternative history: Earth in a funhouse mirror

Fri, 21 Jul 2017 13:33:18 -0400

Thanks to Kellyanne Conway, we have all become familiar with the term “alternative facts,” but how about alternative or counterfactual history? Alternative versions of history have been offered since Classical times. E.H. Carr dismissed them as “parlor games” or “red-herrings” in his 1961 book “What Is History?” But the alt-history concept has been trying to muscle its way into academic respectability since its prominent champion, Niall Ferguson, published an essay collection called “Virtual History” in 1997. Ferguson asked: If a particular, known factor in a historical event has turned out differently, how might subsequent history have changed? Eminent historian Richard Evans was dismissive, wondering whether Ferguson was not so much asking “what if” — reflecting a neutral intellectual curiosity — but “if only,” provoked by a subjective desire for a different outcome from whatever actually took place.

Down to Earth With: Cave microbiologist Hazel Barton

Fri, 21 Jul 2017 10:47:10 -0400

Cave microbiologist Hazel Barton is a professor and the director of the Integrated Bioscience Program at the University of Akron in Ohio. Credit: Dave Bunnell.

In the early 1990s, when Hazel Barton was pursuing her doctorate in medical microbiology at the University of Colorado Health Sciences Center in Denver, she enjoyed exploring caves as a hobby. She never imagined that she would one day incorporate caving into her career.

Evidence of devastating drought found beneath the Dead Sea

Wed, 19 Jul 2017 11:52:18 -0400

The Dead Sea region experienced at least two droughts in the past 200,000 years that were far worse than any in recorded human history. Credit: David Shankbone, CC BY-SA 3.0.

The Dead Sea, a landlocked lake bordered by Israel, Jordan and Palestine, is nearly 10 times saltier than the ocean. And it’s getting saltier. Since the beginning of the 20th century, the water level has dropped by nearly 30 meters, largely because of diversions of the Jordan River, the lake’s primary tributary and the arid region’s main source of fresh water.

Eavesdropping on Old Faithful

Wed, 19 Jul 2017 11:49:33 -0400

Old Faithful's hourly eruptions can usually be predicted to within a 10-minute window. Credit: Mary Caperton Morton.

The Old Faithful geyser in Yellowstone National Park has erupted predictably within a 10-minute window every hour for more than 150 years, but the inner workings that power its regular 30-meter-high eruptive plumes are largely still a mystery. Recent monitoring of the gusher is revealing new secrets about its plumbing system, which may help the National Park Service plan for future infrastructure expansions around the popular attraction.

Nineteenth-century cows muddied Southern California continental shelf

Wed, 19 Jul 2017 11:44:14 -0400

When offshore ecosystems deteriorate, scientists often look at changing ocean conditions, urban runoff or fishing as potential explanations. Cows usually don’t come to mind. But new research investigating the seafloor off the coast of Los Angeles suggests that 19th-century cattle, despite their terrestrial lifestyle, left a lasting impact on the underwater habitat there.

Getting there and getting around Austria's Salzkammergut

Tue, 18 Jul 2017 10:06:53 -0400

Left: Visitors can choose among many quaint inns while staying in Austria's salt district; right: Cable cars throughout Austria's salt region offer easy access to caves, ancient salt works and lookouts with gorgeous views. Credit: both: Lon Abbott and Terri Cook.

“Salzburg boasts Austria’s second-busiest airport, with nonstop flights to cities throughout Europe and connecting flights to a number of North American gateways. Munich, Germany, just 145 kilometers and 1.5 hours away on the A8 autobahn, has direct flights from North America. Picking up a rental car is easy at either airport. Austria’s official language is German, but many Austrians are fluent in English. Road signs are in German but are easily followed by English speakers.

Travels in Geology: Austria's Salzkammergut: World heritage preserved in salt

Tue, 18 Jul 2017 09:57:02 -0400

Stunning Alpine scenery and historic attractions abound in Austria's salt district, the Salzkammergut. Credit: Lon Abbott and Terri Cook.

In Austria’s famous salt district, the Salzkammergut, the long arc of European history, so palpable to North American visitors wherever they travel through Europe, reaches especially far back. Nestled between stunning Alpine peaks and sparkling lakes are numerous salt mines, including those at Hallstatt, which are the oldest known on Earth. Artifacts from the mine date back 7,000 years to the Neolithic, or New Stone Age, period. Surrounding Salzburg, the region’s hub and picturesque home to Mozart, a compact driving loop wends past these mines and a series of other captivating sites that evoke the region’s rich heritage fortuitously preserved in salt.

Delusions of grandeur in building a low-carbon future

Tue, 18 Jul 2017 09:45:03 -0400

Traditional macroeconomic models are an unstable foundation for decision-making when planning for a low-carbon future. Credit: K. Cantner, AGI.

Since April 22, 2016, leaders of 195 nations have signed the Paris climate accord, which starts the process of voluntarily committing to greenhouse gas emissions limits for each country. The agreement was an important signal to the world that the presidents of the two largest economies and greenhouse gas emitters — President Barack Obama of the U.S. and President Xi Jinping of China — were willing to cooperate with the rest of the world on a truly global environmental matter. On June 1, 2017, President Trump stated that he is backing out of the agreement, fulfilling his campaign pledge, but the other signatories indicated they would continue to support the global, voluntary plan for dealing with climate change.

Bottom dropping out of coral reefs

Mon, 17 Jul 2017 08:04:50 -0400

Fish swim amid a coral reef off Islamorada in the Florida Keys. Credit: Bethany Augliere.

Coral reefs provide habitat for 25 percent of all marine life, support fishing and tourism economies, and protect shorelines from surging waves and storms. But since the 1970s, coral populations have been waning because of warming waters, coastal development and pollution. Recently, scientists studying several beleaguered reef systems have discovered an unexpected consequence of their decline — the seafloor around the reefs is eroding, leaving coastal communities more vulnerable to high winds and waves.

In a position to lead: How military technology and innovation can ease the world's water challenges

Fri, 14 Jul 2017 12:15:13 -0400

Water is run through a solar-powered water filtration system at Forward Operating Base (FOB) Hammer in Iraq. Credit: U.S. Army photo by Pvt. Jared Gehmann.

The U.S. military is spread across more than 500 installations worldwide, from small Forward Operating Bases (FOBs) in Afghanistan and Iraq that resemble remote villages without water treatment or sanitation infrastructure, to large domestic bases that operate like established municipalities with aging infrastructure. No matter the size or location of a particular installation, though, the military needs a lot of water.

Getting there and getting around Grand Junction, Colorado

Thu, 22 Jun 2017 10:51:17 -0400

You can enjoy great views of the Book Cliffs as well as delicious wine at many of Grand Valley's locally-owned vineyards. Credit: Terri Cook and Lon Abbott.

Grand Junction is a 4.5-hour drive from major airports in both Denver and Salt Lake City. The smaller but more convenient Grand Junction Regional Airport (GJT) offers nonstop, year-round service to Denver, Salt Lake City, Dallas, Houston, Phoenix and Las Vegas, and seasonal service to Los Angeles.

Travels in Geology: A tale of two rivers: Grand Junction, Colorado

Thu, 22 Jun 2017 10:13:28 -0400

Named for its location at the confluence of two major rivers, Grand Junction, western Colorado’s largest community, is a laid-back city of 60,000. About 50 kilometers from the Utah border, the city is surrounded by tremendous geographic diversity straddling two spectacular landscapes: the classic slickrock sandstone of the American Southwest and the Rocky Mountains’ snow-capped peaks.

Geologic Column: Volcanoes: Awesome and dangerous

Thu, 22 Jun 2017 09:57:51 -0400

A view from space of the Copahue volcano in Argentina. Credit: Public Domain.

Volcanoes never cease to fill me with awe. Volcanism has been a part of Earth’s history since the planet formed about 4.6 billion years ago, and volcanoes continue to punctuate the fiery, dramatic and ongoing creation story of our planet. I have been fortunate to visit several volcanoes around the world while filming science documentaries, and even descended into the vent of Copahue, an active volcano in the Neuquén province of Argentina.

Down to Earth With: Paleoclimatologist Gifford H. Miller

Tue, 20 Jun 2017 21:40:06 -0400

Gifford H. Miller, a professor of geological sciences at the University of Colorado Boulder and associate director of the Institute for Arctic and Alpine Research, has spent years conducting paleoclimate fieldwork in the Arctic and Australia. Credit: Gifford H. Miller.

“Hope for the unexpected.” This motto has pulled paleoclimatologist Gifford H. Miller to remote corners of the world to conduct fieldwork for more than half a century. Miller, a professor of geological sciences at the University of Colorado Boulder (CU) and associate director of the Institute for Arctic and Alpine Research, thrives on the pursuit of knowledge, asking tough questions about the global climate system whose answers have far-reaching implications. But it’s the thrill of unexpected discoveries — of which he’s made many — that keep him returning for more. His discoveries, including the extinction timing of giant birds in Australia, the existence of “zombie mosses” that document the life-cycle of Arctic ice caps, and the finding of lake sediments that tell the story of Iceland’s deglaciation, have led to advances in our understanding of Earth’s climate history and the role humans have played in it.

Geomedia: Mixed media: Geo-art collaboration shifts perspectives on earth materials

Mon, 19 Jun 2017 21:06:32 -0400

Katharine Cashman, a volcanologist at the University of Bristol in England, presented her research on visualizing earth materials at the American Geophysical Union's 2016 fall meeting. Credit: Harvey Leifert.

An attendee explores the geo-art concepts. The work of other attendees hangs above. Credit: Harvey Leifert.

“Arts and Sciences.” The phrase is familiar to students and faculty on most campuses, often serving as the moniker of colleges or other curricular subdivisions within universities. While the pairing suggests a joint enterprise of some sort between the two fields, it might more aptly be termed, “Arts or Sciences,” as curricula rarely encompass both.

Ice (Re)Cap: July 2017

Mon, 19 Jun 2017 20:52:18 -0400

The Barnes Ice Cap (circled in red) on Canada's Baffin Island is one of the few remnants of the massive Laurentide Ice Sheet, which covered much of North America during the last ice age. Credit: Jeff Schmaltz/NASA Earth Observatory.

New global volcanic emissions map debuts

Mon, 19 Jun 2017 20:39:47 -0400

Volcanic sulfur dioxide emissions measured by the Aura satellite are shown in shades of orange in this map of Alaska's Aleutian Archipelago. Credit: Jesse Allen/NASA Earth Observatory.

Volcanoes may not always be erupting ash or lava, but that doesn’t mean they’re not venting other materials. Many, in fact, continuously spew gases like carbon dioxide and sulfur dioxide into the air. In a new study, volcanologists compiled data tracking such releases, collected by NASA’s Aura satellite, into the first global map of volcanic sulfur dioxide emissions.

Magnetic method dates glacial floods in Iceland

Mon, 19 Jun 2017 13:26:43 -0400

Researchers studied flood-displaced boulders like this one in front of the Sólheimajökull Glacier, which overlies Iceland's Katla Volcano, to develop a new tool for dating past flood events. Credit: Thomas Berndt.

In Iceland, volcanoes buried under glaciers occasionally melt huge quantities of ice, setting off massive glacial floods called jökulhlaups. Dating past jökulhlaups helps geologists better understand the eruptive history of Iceland’s many active volcanoes, which, in turn, sheds light on future volcanic hazards. But such dating is no easy task. A new study of magnetic minerals preserved in large boulders moved by floodwaters might provide a new tool in the effort.

Evolution of eyes, not limbs, led fish onto land

Mon, 19 Jun 2017 13:08:40 -0400

Evolutionary advances in aquatic eyesight may have led vertebrates onto land. Credit: ©Callan Bentley, 2017.

In the Middle Devonian, roughly 385 million years ago, the first vertebrates began making their way out of water. For these pioneering fish, the adaptation of fins into limbs facilitated the transition. But in a new study, researchers have found that millions of years before fully functional terrestrial limbs evolved, some fish were developing better eyesight — an evolutionary adaptation they suggest gave an advantage to fish hunting insects near the shore.

New cloud types recognized

Mon, 19 Jun 2017 13:04:49 -0400

A tubular volutus roll cloud takes shape off the coast of Uruguay. Credit: Daniela Mirner Eberl, CC BY-SA 3.0.

Wavy asperitas clouds resemble a rolling, stormy sea. Credit: ©Gary MacArthur.

Familiar clouds like cumulonimbus, cirrocumulus and nimbostratus have some new company. The World Meteorological Organization (WMO) has published a new edition of its International Cloud Atlas, the first revision since 1987. The updated version — released in digital format for the first time — compiles recent observations and introduces about a dozen new terms, such as “asperitas,” which refers to a cloud whose sweeping undulations resemble the surface of a stormy sea, as well as names for clouds induced by wildfires and by human activity. There is even a new cloud species, “volutus,” which describes long, tube-shaped rolling clouds.

Northeast and Midwest U.S. projected to warm faster than national average

Fri, 16 Jun 2017 16:18:28 -0400

The Northeast, including Boston, is projected to warm more quickly over the next few decades than the contiguous U.S. as a whole, according to a recent study. Credit: bobwright, CC0

The U.S. Northeast and Midwest will warm quickly in the coming decades compared to national and global averages, reaching established temperature benchmarks sooner than most of the rest of the country, and the world, according to recent research published in PLOS ONE.

Platinum may point to impact theory for Younger Dryas

Fri, 16 Jun 2017 14:52:51 -0400

Archaeologists found an abundance of platinum — an element that can be associated with cosmic objects like asteroids or comets — at 11 Clovis excavation sites across the United States. Credit: K. Cantner, AGI.

Some large meteorite strikes leave obvious craters on Earth’s surface, while others that hit water or ice or explode in the air may only leave subtle markers in the soil, such as exotic minerals or elevated levels of rare elements like platinum or iridium. In a new study, researchers report spikes of platinum in sediments at archaeological sites across North America, offering new evidence, they suggest, of a major meteorite strike about 12,800 years ago, just before the onset of a global cold period known as the Younger Dryas. The lack of a telltale crater dating to this time, however, has left scientists debating for years whether an impact actually occurred and what, if any, role it had in setting off the cold snap and affecting some of Earth’s human and animal populations.

Comment: A moving target: What you need to know about drone regulations

Fri, 16 Jun 2017 14:34:19 -0400

In 2015, about 700,000 drones were sold in the U.S. In 2016, the number exceeded 2.5 million. And the Federal Aviation Administration (FAA) has estimated that annual sales will reach 7 million in 2020, with fewer than half of those being operated by commercial users. Drones, or unmanned aerial systems (UASs), have gone from expensive tools primarily used for military and other high-end applications to easily accessible devices used widely for recreation, education, research and everyday commercial enterprises. Reduced costs, wide availability and a growing number of models designed for diverse applications have made drones exceptionally popular.

The only Earth: Exploring the link between plate tectonics and life on the blue planet

Thu, 15 Jun 2017 11:31:36 -0400

Credit: NASA.

Earth is the only planet known to have active plate tectonics, and also the only place that hosts life. Could that be a coincidence? It’s possible, but most geoscientists don’t think so. In many ways, it seems plate tectonics was fundamental in setting the stage for biological evolution and for maintaining and sustaining life on Earth.

Whirling "gravel devils" show wind can carry more than just sand

Thu, 15 Jun 2017 11:24:28 -0400

Abraded gypsum blades deposited by a gravel devil. Credit: Kathleen Benison.

A gypsum gravel devil swirls above the Salar Gorbea. Credit: Kathleen Benison.

Sand grains, by definition, are between 0.06 and 2 millimeters in diameter, and they are often thought of by scientists as the largest sediments that wind can transport, with larger sediments simply being too hefty for winds to keep aloft. But strong winds, particularly in tropical storms and tornadoes, are known to move objects far larger than sand over short distances. Now, in the high Andes of Chile on the Salar Gorbea salt flat, evidence has been found of tornadic “gravel devils” whipping across the landscape and transporting gypsum crystals as long as 27 centimeters.

Burying the sky: Turning carbon dioxide into rock

Thu, 01 Jun 2017 20:44:12 -0400

Hellisheidi Geothermal Power Plant, located in southwest Iceland, produces electricity and hot water from the Hengill Central Volcano. Credit: Gunnar Svanberg.

Blocky, moss-covered basalt covers the ground surrounding Iceland’s Hellisheidi Geothermal Power Plant. As acidic rainwater percolates through the landscape, the volcanic rocks slowly dissolve. Some of what dissolves from the rocks — ions of calcium, iron and magnesium — reacts with carbon dioxide in the air to form carbonate minerals. Over thousands of years, these minerals are buried, locking the greenhouse gas underground — and out of the atmosphere — in a persistent, but slow, part of the global carbon cycle.

"The Himalaya Connection": Telling a story of geoscientific exploration on film

Mon, 22 May 2017 11:55:27 -0400

Author Doug Prose films on the flanks of a volcano in central Mongolia during one of the six scientific expeditions featured in "The Himalaya Connection," which explores the Indo-Australian-Eurasian plate collision. The documentary will air on PBS later this year. Credit: Diane LaMacchia.

It was 3 a.m. on our first night in the field. In our dome tent, I was startled awake by a distant rumbling sound, accompanied by a growing trembling of the ground. As a Californian who lives 4 kilometers from the Hayward Fault, and who has ridden out many earthquakes, this felt like the onset of seismic shaking. On this occasion, however, I was camping with a geologic expedition in central Mongolia, which is also earthquake country. Three magnitude-8 or higher quakes, “megaquakes,” have struck here in the past century. But this was no earthquake. As the rumble grew louder I began to make out neighs and snorts: A herd of horses was galloping right for our camp?! How would the speeding horses see through the darkness and rain that night to avoid the dozen tents pitched, exposed and defenseless, on the wide-open meadow? I flashed on the thought that ours was the same terror experienced by the poor souls in the path of a cavalry charge led by Genghis Khan, Mongolia’s 12th-century ruler. We were going to be trampled! Somehow, the horses sidestepped the tents, and after my heart stopped pounding I fell asleep again. In the morning, we confirmed that the trembling hadn’t been an earthquake, nor was it dreamed. The horses were grazing along the river about 100 meters away, and the herders were having tea with our guides around a fire. “Toto,” I said to myself, “I have a feeling we’re not in Kansas anymore.”

Getting there and getting around Kalahari

Mon, 22 May 2017 11:43:32 -0400

It's best not to drive in Botswana after dark to avoid collisions with wildlife. Credit: Lon Abbott and Terri Cook.

“There are three gateway cities to the Kalahari, all of which are at least a day’s drive from the Okavango Delta. Although it’s the farthest (about 12 hours away), the O.R. Tambo International Airport (JNB) in Johannesburg, South Africa, is the region’s largest and often has the best airfares and car-rental rates. Two closer alternatives, each about an eight-hour drive away, are Botswana’s Sir Seretse Khama International Airport (GBE) in Gaborone and Namibia’s Hosea Kutako International Airport (WDH) in Windhoek. Maun (MUB) is Botswana’s primary tourist hub and the delta’s main service town. Most accommodations there provide a free minibus transfer from the airport.

Travels in Geology: Tracking African animals and deranged drainages across the Kalahari

Fri, 19 May 2017 12:03:03 -0400

The local name for Victoria Falls translates as "The Smoke That Thunders." Credit: Lon Abbott and Terri Cook.

After landing in Windhoek, Namibia, on the western edge of the Kalahari Desert, our family embarked on an African adventure with two exhilarating objectives: to see iconic African animals in the Okavango Delta, a major river delta in the middle of the dry Kalahari, and to view the thundering Victoria Falls, a day’s drive from the delta on the desert’s northeastern side. Most tourists consider these two magnificent UNESCO World Heritage sites to be wholly unrelated. But to a geologist, they are inextricably linked via major hydrologic changes that have swept across the region in response to both subtle tectonic movements and major Pleistocene climate fluctuations.

Benchmarks: June 1977: First Excavations at Nebraska's Ashfall Fossil Beds

Fri, 19 May 2017 11:51:19 -0400

The "Rhino Barn" at Nebraska's Ashfall Fossil Beds State Historical Park. Credit: University of Nebraska, Lincoln.

In the spring of 1971, paleontologist Mike Voorhies was mapping rock exposures on a farm in northeastern Nebraska when he wandered into a small ravine that recent heavy rains had swept clean of debris. High on the gully wall, a change in the color of the rock caught his eye, so he decided to scramble up and take a closer look.

Down to Earth With: Biogeochemist Stephen MacAvoy

Fri, 19 May 2017 10:30:06 -0400

Biogeochemist Stephen MacAvoy is an assistant professor and chair of the environmental science department at American University in Washington, D.C. Credit: Stephen MacAvoy.

When Stephen MacAvoy was growing up in the suburbs of Connecticut, most of the animals he encountered were pets: dogs, cats or the occasional bird. But on his annual family trips to the coast of North Carolina, the beach provided a window into an alien world. He collected washed-up blue crabs, snails and other marine organisms, with their intriguing shapes, spines and intricate mouthparts. His mother, a nursing professor, and his father, a business consultant, even allowed MacAvoy to bring his field samples home in a cooler.

The mackerel year: Tambora changed how New England fished

Wed, 17 May 2017 10:22:52 -0400

Fishermen clean mackerel near their saltwater farm on Deer Isle in Maine's Penobscot Bay in 1891. Mackerel fishing increased following the 1815 eruption of Tambora. Credit: NOAA Library, Silver Spring, Md.

The 1815 eruption of Indonesia’s Tambora Volcano led to a 1- to 1.5-degree-Celsius drop in the average global temperature, prompting 1816 to be called the “year without a summer.” New research analyzes weather data and historical records from New England to explain why, in the northeast U.S., 1816 was also called the “mackerel year.” As eruption-induced extreme weather triggered food scarcity in some areas, including a reduction in alewife numbers along the U.S. Atlantic coast, fishermen in the Gulf of Maine turned to mackerel fisheries farther offshore that had been neglected while more easily fished coastal and freshwater species were available.

Monsoon shifts shaped early Chinese cultures

Wed, 17 May 2017 10:19:48 -0400

The landscape near Lake Dali, with elevations of the lake surface during past highstands noted. Credit: Yonaton Goldsmith.

Rapid, climate-driven shifts in monsoon patterns may have shaped ancient Chinese societies, according to new research. And their history could be our future.

Ups and downs of potassium feldspar may play role in clouds and climate

Wed, 17 May 2017 10:09:58 -0400

Potassium feldspar is one of the main mineral components of Yosemite's famous granite, giving it a pinkish hue. Credit: Mary Caperton Morton.

For water vapor in the atmosphere to transform into icy, cloud-forming droplets, it needs a seed around which to condense, such as aerosols, sea salt or bacteria. One of the most effective seeds is mineral dust, in particular potassium feldspar, one of the main ingredients in granite. New research tracking fluxes of potassium feldspar in the atmosphere through geologic time is shedding light on the long-term importance of the mineral in cloud formation and climate feedback cycles.

Timing of famed "Millennium Eruption" pinpointed

Mon, 15 May 2017 21:04:20 -0400

A fossilized tree, killed by the Millennium Eruption of Changbaishan Volcano on the border between China and North Korea, has allowed scientists to pinpoint the date of the eruption. Credit: Clive Oppenheimer.

Changbaishan Volcano in northeastern China, on the border with North Korea (where it’s known as Mount Paektu), is steeped in superstition, having produced devastating eruptions several times in recorded history. Legends that a massive eruption in the 10th century led to the downfall of a regional empire have now been refuted, however, thanks to a new analysis of a fossilized tree killed by the eruption that dates the eruption to after the kingdom fell.

Comment: Kitchen counter geology: Bringing rock identification to a new audience

Mon, 15 May 2017 20:55:08 -0400

Karin Kirk answers questions from attendees of the rock identification workshop at the International Surface Event in Las Vegas in January 2017. Credit: International Surface Event.

As I hoisted my 22-kilogram suitcase onto the scale at the airline check-in counter, the agent joked, “Whatchya got in there, rocks?” We both got a good laugh when I explained that, yes, indeed, the suitcase was completely full of rock samples. I was on my way to Las Vegas, with an entire geology lab in my luggage.

1883 sea rescue informs new model of wind-wave interactions

Mon, 15 May 2017 20:49:00 -0400

The sailing ship Ouragan — depicted in "Les Meteores" by Margolle and Zurcher, 3rd edition, published in 1869 — labors at sea under hurricane conditions. Credit: NOAA Photo Library.

Despite improvements in oceanographic observation, knowledge gaps remain about the interactions between ocean waves and wind blowing over the water’s surface. This is in part due to the difficulty of observing the ocean in high seas and windy conditions. In a new study in Geophysical Research Letters, however, researchers have used a historical record of a treacherous 1883 at-sea rescue — aided by the wave-calming effects of a fish-oil slick — to develop a model of how wind and water interact to form different sizes and types of waves.

When and how did plate tectonics begin on Earth?

Mon, 15 May 2017 20:36:52 -0400

Credit: K. Cantner, AGI.

The basic story of Earth’s formation is familiar to most anyone who has taken a geology course: About 4.6 billion years ago, Earth formed when a rocky nucleus accreted dust and debris left over from the formation of our sun.

Meteorites did not spark Ordovician biodiversification

Mon, 15 May 2017 15:08:48 -0400

Zircon crystals contain trace amounts of uranium and thorium, making them useful for radiometric dating. These highly magnified crystals are about the size of a grain of sand. Credit: Anders Lindskog.

During the Ordovician Period, roughly 470 million years ago, an asteroid the size of a small moon collided with another rocky object in the belt between Mars and Jupiter, shattering the asteroid into billions of pieces. Fragments from the epic collision still occasionally fall to Earth today, making up a large share of the meteorites recovered. But in the immediate wake of the Ordovician event, many pieces rained down on the planet, settling on the surface and in layers of rock forming at the time. In a new study, researchers studying some of these meteorite-rich layers have refined the timescale for the collision. The results bring into question a proposed link between the meteorite bombardment and an evolutionary uptick known as the Great Ordovician Biodiversification Event (GOBE).

"Blob"-related warming contributed to Pacific Northwest ozone spike

Mon, 15 May 2017 15:00:06 -0400

In June 2015, tropospheric ozone levels measured at the observatory on Oregon's Mount Bachelor were more than 20 percent above the decadal average. Credit: Pao Baylon.

In June 2015, instruments on Oregon’s Mount Bachelor recorded mean ozone for the month at 56 parts per billion, more than 20 percent higher than the average level for the 11 years prior. Other stations around the West noted similarly high readings, puzzling scientists over the cause of the rise. In a new study in Geophysical Research Letters, researchers describe a confluence of meteorological conditions that appear to have driven the phenomenon.

Tibetan Plateau populated long before advent of agriculture

Mon, 15 May 2017 14:18:53 -0400

Due to the harsh living conditions of the Tibetan Plateau — which has an average elevation over 4,500 meters — archaeologists have long assumed that people didn’t live in the Himalayan high country until after the adoption of agriculture in this region of the world, about 3,600 years ago. But a new study of a trove of handprints and footprints found around a fossilized mud spring in Tibet is suggesting that people may have lived here as early as 13,000 years ago.

Silk Road routes may have followed the herds

Thu, 04 May 2017 09:42:16 -0400

A herder leads sheep through mountainous terrain in Uzbekistan. The routes established by ancient nomadic herders through the highlands of Central Asia may have paved the way for Silk Road paths, according to recent research. Credit: Michael Frachetti

The Silk Road — the ancient trade route that stretched thousands of kilometers from China to the Mediterranean — often calls to mind images of large camel caravans trekking for months across deserts and over mountains, carrying luxurious linens, spices and gems between distant lands. In reality, the “road” comprised a network of many shorter relays between neighboring areas, with goods often changing hands many times in cities, rural villages and even remote trading outposts. The webbed nature of the network has long complicated archaeological efforts to map exactly where and how the Silk Road developed. In a new study in Nature, researchers have illuminated likely routes of Silk Road travelers through a region of particularly challenging terrain — mountainous Central Asia — with the help of an innovative mapping method.

And then there was one: Ceres' disappearing ice volcanoes

Thu, 27 Apr 2017 12:26:49 -0400

A simulated perspective view of Ahuna Mons, a cryovolcano on Ceres, with the elevation exaggerated by a factor of two. Credit: NASA

Earth has numerous volcanoes, both active and extinct — some of which continue to tower over landscapes long after they finished erupting. On the chilly dwarf planet Ceres, however, scientists have identified just a single volcano — an ice-erupting cryovolcano — raising questions about whether others ever existed there and, if so, what happened to them. In a new study, researchers suggest that Ceres has likely had other volcanoes, but that, over time, their icy slopes have been flattened beyond recognition.

Geomedia: Film: 'Written on Water': A Modern Tale of a Dry West

Thu, 20 Apr 2017 11:12:57 -0400

Filmmaker Merri Lisa Trigilio. Credit: Merri Lisa Trigilio.

An endless patchwork of circular fields surrounds the small West Texas town of Olton. The unnatural shapes and sharp boundaries of the brown and green fields result from center-pivot irrigation systems that pull water from the Ogallala Aquifer and allow more crops to grow than the semi-arid landscape would otherwise allow. On these dusty farms and within town offices a drama is unfolding over what to do as irrigation wells run dry.

Sea-surface temperatures during last interglacial similar to modern day

Wed, 19 Apr 2017 20:02:45 -0400

During the last interglacial period, global sea levels were higher than today but sea-surface temperatures were comparable. Credit: CC0, public domain.

During the last interglacial period, between 129,000 and 116,000 years ago, global sea levels were 6 to 9 meters higher than at present. Scientists have long wondered how global atmospheric and ocean temperatures then compared to modern times, but efforts to reconstruct such temperatures have often fallen short. In a new study, researchers who compiled past records of sea-surface temperatures (SSTs) have revealed that SSTs during the last interglacial were similar to modern day temperatures. But, the similarity doesn’t necessarily predict a future surge in sea levels.

Fossil forest recorded ancient sunspots

Wed, 19 Apr 2017 14:16:33 -0400

A cross section of fossilized wood from the Permian-aged Chemnitz Petrified Forest showing 75 tree rings. Credit: L. Luthardt and R. Roessler.

The sun’s surface is home to dark, relatively cool blotches of high magnetic activity known as sunspots, which vary in number over a roughly 11-year cycle. In a new study in Geology, scientists found evidence of this solar cycle dating back 290 million years to the Permian Period.

Grapes reveal impacts of sulfur-rich Samalas eruption on 13th-century climate

Wed, 19 Apr 2017 14:05:44 -0400

Lake Segara Anak fills the caldera formed during Samalas' 1257 eruption. Credit: Petter Lindgren.

The A.D. 1257 eruption of the Indonesian volcano Samalas sent an ash plume an estimated 43 kilometers into the sky in one of the most sulfur-rich eruptions of the last 7,000 years. A new study using tree rings, ice cores and historical records investigates how this colossal eruption impacted climate across the Northern Hemisphere, finding that the eruption triggered severe cold in some regions, while other areas were less affected. The pattern could be explained by the behavior of sulfate particles in the atmosphere, researchers suggest.

Travels in Geology: Geo-diversity and geologic history in the North West Highlands of Scotland

Wed, 19 Apr 2017 13:54:35 -0400

The North West Highlands of Scotland feature rugged mountains and gorgeous valleys with a rich geological history. Credit: Summer Brown.

The North West Highlands of Scotland are sparsely populated, with rugged mountains and gorgeous valleys featuring a rich geological history. The area has the oldest rocks in the United Kingdom as well as some young landscapes freshly sculpted by ice sheets during the last glaciation. Early geological explorations and explanations of the North West Highlands proved perplexing and contentious, in part because the rocks of this region span two-thirds of Earth’s history in age. Additionally, there are, in places, sedimentary layers sandwiched between metamorphic packages of gneiss and schist. How did this happen? Was the schist deposited like a sedimentary rock atop the sandstone and limestone? Was it a former sedimentary layer that for some reason was exceptionally metamorphosed relative to the layers beneath it? Throw in three separate unconformities and the picture becomes even more muddied. You start to see why multiple generations of British geology students have traveled here for field camps.

Did Jurassic tectonics lead to supergiant oilfields?

Tue, 18 Apr 2017 12:26:44 -0400

Rapid tectonic movements that shuttled the Arabian Plate from near the equator to the southern tropics and back again in the Middle and Late Jurassic may have led to the formation of Arabia's giant oilfields, including the massive Ghawar field. Credit: K. Cantner, AGI.

More than 6 percent of global oil production comes from a single oilfield: the supergiant Ghawar oilfield in eastern Saudi Arabia, which produces more than 5 million barrels of crude oil every day. In a new study in GSA Today exploring the origins of this vast oilfield, researchers have found that extensive tectonic plate movements during the Middle and Late Jurassic may have created the conditions necessary for the formation of the Ghawar and several other oilfields across the Middle East.

Venezuela, Central Africa are Earth's lightning hot spots

Tue, 18 Apr 2017 12:18:23 -0400

Thunderstorms occur roughly 297 days per year above Lake Maracaibo in Venezuela. Credit: NASA.

People who live around Venezuela’s Lake Maracaibo call it a “lighthouse.” The lake’s “never- ending storm” has been written about for centuries, and the incessant lightning there has even helped guide Caribbean sailors. Data from NASA’s Tropical Rainfall Measuring Mission (TRMM) has now confirmed that Lake Maracaibo is Earth’s top lightning hot spot.

Tropical rainfall shifts resulted in greener Sahara

Tue, 18 Apr 2017 12:14:56 -0400

Thousands of years ago, the Sahara was dotted with lakes and vegetation. Credit: Wonker, CC BY 2.0.

Six thousand years ago, the Sahara — today the world’s largest nonpolar desert, stretching over an area larger than the contiguous United States — was dotted with lakes and vegetation. Rock paintings from that time depict a much wetter landscape, and show elephants, hippos, antelope and many other animals living in the region.

Massive dust storm caused by climate, not conflict

Tue, 18 Apr 2017 12:09:21 -0400

A massive dust storm, seen here on Sept. 8, 2015, in NASA MODIS imagery, swept across the Middle East in late summer 2015. Credit: NASA Worldview.

In August and September 2015, a massive dust storm swept across the Middle East, engulfing seven nations in sand thick enough to ground flights, trigger respiratory distress for many, and obscure the region from satellites. At the time, the unprecedented size of the storm was blamed on the ongoing conflict in Syria, with unusual amounts of dust being raised from abandoned agricultural lands and increased military traffic. But a new study cites a combination of climatic factors and weather as the more likely culprits.

Neonicotinoids: Prominent pesticides escape into the environment

Fri, 14 Apr 2017 09:48:30 -0400

Credit: K. Cantner, AGI.

The 1990s was a watershed era in pest control — and, by extension, agriculture — thanks to a particular bit of chemical innovation. With the emergence of a compound called imidacloprid onto the insecticide market, farmers — from those growing rice, corn and other staples, to orchard owners cultivating fruit trees, to backyard gardeners tending vegetable patches — had a powerful new tool with which to combat aphids, beetles, weevils, whiteflies and a host of other insects with a knack for damaging crops.

Six new deep-sea species discovered

Thu, 06 Apr 2017 10:11:31 -0400

This mineralized deep-sea chimney, named "Jabberwocky" by researchers, is in the early stages of growth and provides habitat for many species near the Longqi hydrothermal vent site. Credit: University of Southampton.

About 2,000 kilometers southeast of Madagascar and 2.8 kilometers below the surface of the Indian Ocean, scientists have discovered six never-before-seen animal species living around deep-sea hydrothermal vents. The creatures were spotted by a remotely operated vehicle during an expedition in 2011 to a site called Longqi, or “Dragon’s Breath,” around which stand mineralized vent chimneys — some more than two stories tall — that are rich in copper and gold. Genetic testing confirmed the novelty of the animals, which include new species of polychaete worms and limpets as well as a previously unknown species of hairy-chested “Hoff” crab, named for actor David Hasselhoff.

Breakup of Pangea led to thicker oceanic crust

Thu, 06 Apr 2017 10:09:41 -0400

This map, created by researchers at the University of Texas at Austin, depicts the ages of ocean crust in millions of years before present (Ma). Warm shades represent younger crust and cool shades represent progressively older crust. Modern mid-ocean spreading ridges are indicated by yellow lines. Credit: Harm Van Avendonk.

Oceanic crust formed at mid-ocean spreading centers, like the Mid-Atlantic Ridge, is recycled back into the mantle at subduction zones. Aside from isolated chunks that might be even older, the oldest crust found on Earth today is thought to be about 200 million years old. This old crust, portions of which are found along the outer margins of the Atlantic, Pacific and Indian oceans, is much thicker than the crust being produced today — in some places by almost 2 kilometers — according to a new study, a finding that may suggest that Earth’s supercontinent cycle affects how Earth’s interior cools.

Shale boom could fuel batteries

Thu, 06 Apr 2017 09:59:06 -0400

Water produced from oil and gas development in shale formations could provide lithium needed for batteries. Credit: Chris Boyer, Kestrel Aerial Services, Inc., CC BY-ND 2.0.

By Yael R. Glazer, Jamie J. Lee, F. Todd Davidson and Michael E. Webber

Geologic Column: Evolution of an ape-man

Thu, 06 Apr 2017 09:09:08 -0400

The title page to Charles Darwin's "On the Origin of the Species", published in 1859. Credit: Public Domain.

By the time I was 12, I had identified the greatest writer in the world. His name was Edgar Rice Burroughs and he wrote adventure stories about an ape-man named Tarzan. Burroughs described him as having a “straight and perfect figure muscled as the best of the ancient Roman gladiators must have been muscled, and yet with the soft and sinuous curves of a Greek god.” You could see at a glance his “wondrous combination of enormous strength with suppleness and speed.” Tarzan was human, but he’d been orphaned in Africa and raised by a she-ape in the jungle. That made him an ape-man for sure in any kid’s estimation. The first Tarzan story appeared in 1912, but the most significant date for ape-men was half a century earlier, in 1859, when Charles Darwin published “On the Origin of Species,” which encouraged the search for a real ape-man called the “missing link.”

To find a mate, go big or go small, just don't go medium

Wed, 29 Mar 2017 14:48:45 -0400

New research provides an explanation for the bimodality in male ornamentation seen in some animal species, such as in male dung beetles, which can either have large horns or no horn at all. Credit: Alex Wild.

The showy features of male animals are often advantageous for attracting mates. Yet these same traits can also prove harmful: A peacock’s long, many-eyed feathers — great for enticing females — can get in the way if a predator gives chase, and a red deer’s elaborate antlers can become stuck in branches, potentially trapping the animal. In a new study, researchers report that a distinctive bimodality in male ornamentation occurs in some species, suggesting that when it comes to successfully courting females, it pays for males to either have the flashiest, most elaborate ornaments, or no such parts at all.

Soil acidity changes quickly from place to place

Wed, 29 Mar 2017 14:46:24 -0400

This global soil acidity map shows acidic areas in red and alkaline areas in blue. Credit: University of California, Santa Barbara.

The acidity of soils, which affects soil fertility, depends largely on a region’s climate. What has been less clear is just how abrupt — or gradual — shifts in acidity are at the boundaries between adjacent regions with different climates. In a new study in Nature, scientists report that acidity transitions are indeed abrupt, and the results may provide a glimpse into how plant communities will evolve as the planet’s climate continues to change.

Maui reef degradation linked to contamination in coastal groundwater

Wed, 29 Mar 2017 14:25:27 -0400

Honolua Bay, Maui, a designated marine life conservation district, was one location studied by researchers examining links between land use, water quality and coral reef health at coastal sites around Maui. The bay is surrounded by a watershed featuring potential sources of nutrient runoff from human activities, such as golf courses and sewer systems. Credit: Hawaii Savvy, CC BY 2.0.

Submarine groundwater discharge — the flow of fresh and brackish groundwater from land to sea — can transport contaminants to coastal ecosystems. But little is known about the direct impacts of this process on marine communities. In a new study published in PLOS ONE, researchers examined links between land use, water quality and coral reef health at coastal sites around Maui, finding that anthropogenic contaminants delivered via submarine groundwater are a source of chronic stress to nearshore marine ecosystems.

Seafloor volcanism linked to glacial cycles

Wed, 29 Mar 2017 13:57:37 -0400

Sea-level changes related to glacial and interglacial cycles may affect magma production at mid-ocean spreading ridges. Credit: K. Cantner, AGI, and Julia Rosen.

Eruptions from seafloor volcanoes and cycles of global glaciations may seem unrelated, but new research suggests otherwise, indicating that pulses of volcanism at mid-ocean ridges might have influenced glacial and interglacial periods during the latter half of the Pleistocene.

Getting there and getting around Easter Island

Fri, 24 Mar 2017 08:45:57 -0400

Easter Island offers plenty of chances to surf, snorkel and fish in the South Pacific. Credit: Terri Cook and Lon Abbott.

“Easter Island has just one gateway, tiny Mataveri International Airport (IPC), to which only one airline, the Chilean carrier LATAM, offers regular service. This includes one flight weekly from Tahiti, as well as daily service from Santiago, a five-hour flight. Airfares are high, ranging from about $400 to $1,500 round trip. The island’s unusually long runway once served as an emergency U.S. space shuttle landing site; today, it allows LATAM to land large Boeing 787s there, a rarity among small islands.

Travels in Geology: Easter Island's enduring enigmas

Thu, 23 Mar 2017 13:10:23 -0400

After being knocked down by a tsunami in 1960, the 15 moai perched on Ahu Tongariki were restored a few decades later. Credit: Terri Cook and Lon Abbott.

Few destinations are as steeped in mystique as Easter Island. Located in the southeastern Pacific nearly 3,700 kilometers west of Chile, and more than 2,000 kilometers from the nearest inhabited land, Easter Island is one of the most isolated places on the planet. The lonely isle is renowned for its remarkable moai — massive stone carvings of human-like figures with oversized heads — that for centuries have stood watch over this small speck of land. The moai’s original purpose, as well as the means by which they were transported and erected, remains shrouded in mystery; for some, the figures’ eternal stares have come to symbolize societal collapse due to environmental degradation, although the details of the theory behind this view have been vigorously contested. Also controversial, at least among geologists, is the origin story of the island itself and whether or not it was formed by a hot spot. While planning a recent trip to Chile, we couldn’t resist the opportunity to visit Easter Island’s storied shores and experience these enduring enigmas first-hand.

El Niño gets animated

Mon, 20 Mar 2017 13:16:53 -0400

Warm water pools in the eastern tropical Pacific in this screenshot from a new animation recreating the strong El Niño event of late 1997 and early 1998. Credit: ARC Center of Excellence for Climate System Science/National Computational Infrastructure.

In the winter of 1997 and 1998, a powerful El Niño pattern in the Pacific Ocean caused billions of dollars in damage from flooding and extreme weather worldwide. Now, a new animation of the event is highlighting the complex feedbacks that conspired to create such a devastating climate cycle.

White Cliffs of Dover on the retreat

Mon, 20 Mar 2017 13:03:07 -0400

The White Cliffs of Dover. Credit: Martin Hurst.

England’s iconic White Cliffs of Dover tower 100 meters over the English Channel and, historically, were often the first and last view of England for sea-faring travelers. New research investigating the erosion history of the steep chalk cliffs suggests that they have been retreating far faster over the last 150 years than they once did.

Tectonics trigger underwater volcanism

Mon, 20 Mar 2017 12:35:00 -0400

The East Pacific Rise runs along the Pacific seafloor from southern California to Antarctica. Credit: K. Cantner, AGI.

In 2006, a large eruption occurred on the seafloor about 1,000 kilometers off the coast of Mexico. Geochemical dating of the erupted lava suggested the event went on for up to 10 months. Now, researchers taking a closer look at seismic and audio recordings made during the event have found that the eruption likely occurred over a much shorter period — a matter of days instead of months. The findings shed light on the sequence of events leading up to the event, as well as on the mechanisms of such seafloor eruptions.

Geomedia: Radio: "The Infinite Monkey Cage" takes listeners to the edge of the universe and beyond

Wed, 15 Mar 2017 14:26:39 -0400

The "Infinite Monkey Cage," a BBC radio show and podcast hosted by comedian Robin Ince (left) and physicist Brian Cox (right), provides an irreverent and witty take on science. Credit: BBC/Richard Ansett.

“Science is not about finding the right answer, it’s finding the least wrong answers,” quips physician and science writer Ben Goldacre, a guest on “The Infinite Monkey Cage,” a BBC radio show and podcast that casts an irreverent eye on big scientific questions. Goldacre was commenting on the definition of science, but this philosophy — that science is a constantly evolving pursuit, in which all ideas are valid until data and time prove them wrong — is also the refreshing and approachable premise of this witty show.

Early spring thaw triggers Arctic greenhouse gas release

Tue, 14 Mar 2017 18:59:29 -0400

Researchers check on a gas flux measurement tower in Alaska after the annual spring thaw. Credit: Stan Wullschleger.

During the few short months of Arctic summer, plants and animals race to grow and reproduce, fueling the most active time in the Arctic carbon cycle. But in a new study, researchers examining one corner of the Arctic demonstrate that ecosystems in the icy north aren’t entirely shut down during the offseason, with pulses of carbon dioxide and methane released some years starting during the first spring thaw.

Pyroclastic flows, not caldera collapse, caused Santorini tsunamis

Tue, 14 Mar 2017 18:56:33 -0400

The massive 1650 B.C. eruption of Santorini caused the volcano to collapse, producing a caldera. The volcano is now a series of islands. Credit: NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team.

The 1650 B.C. eruption of the Greek island volcano Santorini, located in the Aegean Sea, triggered tsunamis that heavily damaged coastal towns and disrupted vital shipping and trade operations, events thought to be important factors in the demise of the ancient Minoan culture.

Earth's magnetic field illuminates ocean temperatures

Tue, 14 Mar 2017 18:53:58 -0400

An illustration of Earth's fluctuating magnetic field lines. Credit: Conceptual Image Lab at NASA's Goddard Space Flight Center/Matthew Radcliff, producer.

As Earth warms, the atmosphere isn’t the only place where temperatures are rising — the oceans are absorbing most of the excess heat, but precisely how much is unclear. Using recently launched satellites that can measure subtle fluctuations in Earth’s magnetic field, researchers are devising a method that may help refine ocean temperature measurements and clarify how much heat the oceans are storing.

How soil management could help reduce greenhouse gas concentrations

Thu, 16 Feb 2017 15:51:12 -0500

Accounting for soils in greenhouse gas-related policies could benefit both emissions reduction and sequestration efforts, researchers say. Credit: Jing, CC0 Public Domain

As scientists continue studying the web of natural and anthropogenic processes that affect Earth’s climate, discussions about how to limit global warming have included proposals both to cut emissions and to increase sequestration of greenhouse gases through a variety of methods.

Getting there and getting around Mount Katahdin

Thu, 16 Feb 2017 11:30:53 -0500

"Sign" marking the logging road to Blueberry Ledges Trail in Baxter State Park. Such signs are common in the region. Credit: Bethany Augliere.

Mount Katahdin in Baxter State Park is about 120 kilometers northwest of Bangor, Maine, and its international airport. Once in Maine, you will need a car to get around. You can rent one at the airport or drive in from another large regional city like Boston. Plan to visit in the summer months before Oct. 15, when the campgrounds close. Bear in mind, they can be closed earlier due to weather.

Travels in Geology: Exploring Maine's magnificent Mount Katahdin

Thu, 16 Feb 2017 11:16:33 -0500

At about 1,605 meters, Mount Katahdin in Baxter State Park is the highest mountain in Maine. Credit: Bethany Augliere.

After weeks of anticipation and constant checks of weather forecasts to find a day when the skies were likely to be clear, I decided the early fall morning had finally arrived to hike Mount Katahdin — the highest mountain in Maine at 1,605 meters. I woke up at 5 a.m., crawled out of my sleeping bag, got dressed and turned on my headlamp to begin the trek.

Ice (Re)Cap: March 2017

Thu, 16 Feb 2017 11:08:44 -0500

Large, tabular icebergs float in Pine Island Bay, part of the Amundsen Sea off the coast of West Antarctica. Credit: James Smith.

Life on land 300 million years earlier than thought

Thu, 16 Feb 2017 11:06:11 -0500

Life emerged on land about 300 million years earlier than previously thought, according to a new study in Geology by scientists who discovered minerals in 3.22-billion-year-old rocks that they suggest could only have formed with the help of biological processes.

Beneath one volcano, enough water to fill Lake Superior

Thu, 16 Feb 2017 10:54:04 -0500

Beneath a Bolivian volcano called Cerro Uturuncu sits one of Earth’s largest-known magma reservoirs, the Altiplano-Puna Magma Body (APMB), which may have a volume as large as 500,000 cubic kilometers. Dissolved in the APMB magma, scientists report in a new study in Earth and Planetary Science Letters, is enough water to fill Lake Superior or Lake Huron — two of the largest lakes in the world.

Geologic Column: Rebirth on the vernal equinox

Wed, 15 Feb 2017 15:18:53 -0500

March is about rebirth. Credit: Public Domain.

March is a particularly tempestuous month. The Anglo Saxons called it “Hrethmonath,” which translates as “rough month.” The name referred to March’s blustery winds that often blow with a force unfelt all winter, and which make March a great month for kite flying and a common time for tornadoes to strike.

Down to Earth With: Cave scientist and paleoclimatologist Kathleen Johnson

Thu, 09 Feb 2017 09:53:48 -0500

Kathleen Johnson is an associate professor in the Department of Earth System Science at the University of California, Irvine (UCI), where she studies speleothems to investigate past climates. Credit: Kathleen Johnson.

Paleoclimatologist Kathleen Johnson has some advice for anyone interested in tropical cave science: befriend experienced cave guides and beware of venomous snakes, ubiquitous bats and Frisbee-sized spiders.

Geomedia: Film: Exploring Florida's aquifers with filmmaker Tom Fitz

Thu, 09 Feb 2017 09:45:13 -0500

Filmmaker Tom Fitz describes the first time he found himself sitting, alone, more than 20 meters below Earth’s surface and about 300 meters into an underwater cave: He was waiting in position to film a sequence of divers swimming through a narrow passageway as their lights illuminated the chamber for his new, yet to be named, documentary. “I was suddenly in absolute, complete black,” Fitz says. “The kind of darkness that we rarely experience.”

Early Pacific seafarers set sail in El Niño years

Thu, 09 Feb 2017 09:38:34 -0500

Credit: K. Cantner, AGI.

Even with modern airplanes and ships, the far-flung islands of Tonga, Samoa, Hawaii, Micronesia and Fiji are difficult to reach. Thousands of years ago, the seafarers who first settled the islands had a much more arduous journey, sailing thousands of kilometers and navigating by the stars. According to a new study, these intrepid travelers may have gotten a boost from weather associated with El Niño-Southern Oscillation patterns, which sweep through the Pacific every three to seven years.

Ants developed farming millions of years ago

Thu, 09 Feb 2017 09:12:04 -0500

A new study in Nature suggests that ants may have invented agriculture as much as 3 million years before humans.

On the Fijian islands of Viti Levu, Vanua Levu and Taveuni, the ant species Philidris nagasau actively cultivates at least six species of Squamellaria plants, using the plants for both food and shelter. All of the Squamellaria are epiphytes, or plants that grow on other plants, using their hosts for support and nutrients. The ants were observed gathering seeds from the fruits of the Squamellaria and inserting them into crevices in host trees. Worker ants constantly patrolled the seeds and, as the seedlings took root in the host, they defecated in the crevices, fertilizing the young plants. As the plants mature, they form hollow chambers at their bases, which the ants were observed using for nests. The ants also harvested the Squamellaria fruit, eating the flesh and collecting seeds for planting.

Early humans dealt with Ethiopian supervolcanoes

Wed, 08 Feb 2017 14:05:12 -0500

Modern geochronological techniques were used to calculate the age of volcanic deposits and build an eruptive history for the volcanoes of the Ethiopian Rift. Credit: William Hutchison.

About 200,000 years ago, modern humans evolved in East Africa, including in what’s now Ethiopia. They — like earlier hominins who had preceded them — likely encountered occasional explosive eruptions spewing ash and lava into the air and onto the landscape, according to a new study in Nature Communications.

To cool the planet, volcanoes of the future will need more firepower

Tue, 07 Feb 2017 14:29:46 -0500

On June 15, 1991, Mount Pinatubo sent a plume up 40 kilometers into the stratosphere. Credit: David H. Harlow, USGS.

Explosive volcanic eruptions can spew sulfur gas into the stratosphere — the layer of the atmosphere above where most clouds and weather occur — where it forms sulfate aerosols that reflect sunlight back into space and cool the planet. Now, researchers investigating how volcanic plumes could be affected by projected anthropogenic warming have found that, as temperatures rise, it becomes more difficult for volcanic plumes to reach the stratosphere.

Broadening ocean current could carry less heat poleward with climate change

Tue, 07 Feb 2017 14:24:37 -0500

University of Miami technician Mark Graham attaches an acoustic current meter to a mooring line during instrument deployment operations in the Agulhas Current in November 2011. Credit: James Campbell.

Some ocean currents, like the Agulhas Current in the southwestern Indian Ocean, act like giant air conditioners, moderating Earth’s climate by shuttling heat from the equator toward the poles. The Agulhas is one of the largest and fastest currents in the world: Flowing southwest along the east coast of Africa, it stretches almost 1,500 kilometers and transports about 70 million cubic meters of water every second toward the South Pole at peak speeds upward of 7 kilometers per hour.

A mysterious first

Fri, 27 Jan 2017 11:46:49 -0500

The first six women to reach the South Pole — on Nov. 12, 1969. From left: Pam Young, Jean Pearson, Terry Tickhill Terrell, Lois Jones, Eileen McSaveney and Kay Lindsay. Credit: U.S. Antarctic Program.

Women sailed around the sub-Antarctic islands well before Caroline Mikkelsen or Ingrid Christensen’s journeys, usually accompanying their sailor husbands. Maori navigators are known to have traveled these waters for centuries. Although Christensen and Mikkelsen are credited with Antarctic firsts, some people think another woman may have come before. In her book “Women on the Ice,” Elizabeth Chipman, an Australian writer who visited and worked in Antarctica in the 1960s and ‘70s, writes of a woman who was shipwrecked on Campbell Island, 700 kilometers south of New Zealand, in 1835. The woman was rescued four years later by two sealing ships that then sailed farther south toward the Antarctic mainland; perhaps those on board got a glimpse of the icy continent. On the way back to England, however, one of the ships was lost at sea and she died. As the woman’s name wasn’t recorded in the log of the surviving ship, her story, and her potential first, is lost to history.

Getting there and getting around the Dead Sea rift

Thu, 26 Jan 2017 11:16:35 -0500

Most flights into Israel from the U.S. and Europe go through Ben Gurion International Airport (TLV), located 19 kilometers south of Tel Aviv. The most flexible and convenient option for getting to and from the airport and for exploring the region is to rent a vehicle; the airport and downtown Tel Aviv offer many rental options. Cars drive on the right, and road signs are marked in Hebrew and English. From the airport, the Dead Sea is about a three-hour drive (170 kilometers).

Travels in Geology: The Dead Sea Rift: Salty soaks and ancient earthquakes in a storied land

Thu, 26 Jan 2017 11:01:47 -0500

The Roman ruins of Masada offer a panoramic sunrise view over the Dead Sea Rift. Credit: Lon Abbott & Terri Cook.

We were raised in a culture strongly influenced by biblical stories. Tales like Saul’s pursuit of David through the Judean wilderness, the destruction of Sodom and Gomorrah, and the fate of Lot’s wife are touchstones that have shaped our society’s moral and ethical norms and echo through Western literature. The geology of the Dead Sea Rift, where those tales unfolded, is integral to their content.

Geologic Column: The gift of intelligence

Thu, 26 Jan 2017 09:45:04 -0500

Illustration of Earth's land mammals by total weight, shown for humans, pets and livestock, and wild animals. Credit: Illxkcd.com/1338/.

In 1960, astronomer and astrophysicist Frank Drake pointed a telescope of the National Radio Astronomy Observatory toward two nearby stars. He was looking for signals that were artificially generated. His was the first modern search for extraterrestrial intelligence (SETI). Drake reasoned that the stars could anchor orbiting planets where life might have taken hold. Over eons, life on the planets might have proliferated, diversified and grown in complexity. Natural selection would have picked winners from among the blossoming variety, and intelligent life — with the ability to sense an environment and analyze information received, as well as to project future scenarios and choose among them — would seem the likely eventual winner. This intelligence could have been used to create wondrous technologies, potentially allowing for communication over interstellar distances.

Benchmarks: February 5, 1931 and February 20, 1935: Antarctic firsts for women

Wed, 25 Jan 2017 15:25:20 -0500

Norwegian Ingrid Christensen (left), along with her friend Mathilde Wegger, sitting on the deck of the M/S Thorshavn in 1931. They were the first women on record to see Antarctica on Feb. 5, 1931. Credit: Norwegian Polar Institute.

Norwegian Caroline Mikkelsen was originally credited as the first woman to set foot on Antarctica. On Feb. 20, 1935, she made landfall at the Vestfold Hills in East Antarctica. The distinction was later bestowed to Ingrid Christensen and three companions. Credit: Norwegian Polar Institute.

Wegger with a penguin taken aboard the Thorshavn. Credit: Norwegian Polar Institute.

We can only guess what Caroline Mikkelsen was thinking on Feb. 20, 1935, as she sipped her coffee, resting on a rocky hillside surrounded by the noise and stink of thousands of Adélie penguins. Minutes before, she had become the first woman to set foot in Antarctica and had helped hoist the Norwegian flag into place atop a rock cairn, claiming Norway’s influence in the land. Was she thrilled? Proud? Did she care about the significance of her presence there? We don’t know — little was recorded about the event; and most of what was recorded was lost for decades, resigning the episode, for a time, to footnote status amid the annals of a continent shrouded in mystery and a culture of polar exploration enraptured by the heroic and masculine deeds of the male explorers who had come before.

Down to Earth With: Mountain biking geologist Kurt Refsnider

Wed, 25 Jan 2017 15:16:13 -0500

Growing up in Minnesota, Kurt Refsnider spent a lot of time exploring old clay and limestone quarries along the Minnesota River, where he collected marine fossils. While on a camping trip with his family at age 8, he visited the Burgess Shale in Banff, Canada, and learned about the exquisitely preserved soft-body fossils of Precambrian marine fauna. The experience initially made him want to become a paleontologist. But as he grew up, the glacial landscapes of the upper Midwest drew his attention and he decided to study geology instead.

Geomedia: Books: Exploring "The Worst of Times"

Wed, 25 Jan 2017 15:13:01 -0500

"The Worst of Times: How Life on Earth Survived Eighty Million Years of Extinctions," by Paul B. Wignall, Princeton University Press, May 2017, paperback, 978-0691176024. (Hardcover, 2015, 978-0691142098).

Every reader of this magazine knows something about mass extinctions. But few of us know as much as Paul B. Wignall, a professor of paleoenvironments at the University of Leeds in England who studies mass extinctions. In 1997, he co-authored with Anthony Hallam a scholarly volume titled “Mass Extinctions and their Aftermath.” Now, his first book aimed at a popular audience, “The Worst of Times: How Life on Earth Survived Eighty Million Years of Extinctions,” has been issued in paperback.

Liverworts, not moss, dominated Earth's early terrestrial ecosystems

Wed, 25 Jan 2017 13:58:56 -0500

Moss carpets colonize recent lava flows in southern Iceland. Credit: Ria Mitchell.

Moss, the springy green plant that blankets forest floors, has been heralded as the generator of large amounts of oxygen to Earth’s atmosphere during the Paleozoic. In a new study, however, researchers suggest that it could have been the overlooked relative of moss — liverworts — that dominated early terrestrial ecosystems and thus had more to do with reducing high carbon dioxide levels in the atmosphere at the time and cooling climate globally.

Comment: Crazy times in the Arctic

Mon, 23 Jan 2017 19:56:01 -0500

The Arctic sea-ice extent for December 2016 was 12.10 million square kilometers — a record low for this time of year. The magenta line shows the 1981 to 2010 median extent for December. The black cross indicates the geographic North Pole. On Dec. 22, weather models showed temperatures near the North Pole about 17 to 22 degrees Celsius above average. Credit: NSIDC.

I have studied the climate of the Arctic since the early 1980s. In that time, I’ve had a front row seat from which to observe the radical transformation of the region as I’ve been involved in research on the Arctic’s atmosphere, sea ice, ocean circulation, snow cover, permafrost and hydrologic cycle. For more than a century, it has been recognized that, as atmospheric greenhouse gases increase globally, the resulting warming and its effects would be most pronounced in the Arctic. These predictions have been realized: Over the past several decades, the Arctic has warmed at roughly twice the rate as the rest of the planet. And the Arctic Ocean’s sea-ice cover, which waxes and wanes with the seasons, growing through autumn and winter and shrinking through spring and summer, has gradually shrunk.

Small floods can carve big canyons

Thu, 19 Jan 2017 13:41:27 -0500

Moses Coulee, amid the Channeled Scablands in Washington state, was carved by floods that burst from massive, naturally dammed glacial lakes during the last ice age. Credit: Williamborg.

Through the early 20th century, geologists argued over how the giant canyons of the Channeled Scablands in Eastern Washington were formed. Ultimately, a theory proposed by J Harlen Bretz in the 1920s — that the canyons were carved by catastrophic, short-lived outbursts of floodwaters unleashed when natural dams holding back glacial lakes collapsed — was shown to be correct. Controversy still exists, though, about the size of these ancient floods.

Robotic mussels track temperature change

Thu, 19 Jan 2017 13:36:16 -0500

Researchers deployed fake mussels equipped with internal thermometers to record temperatures in living mussel beds. Credit: Brian Helmuth.

Among the crashing waves of rocky shorelines, tiny robotic mussels are providing scientists with insight into climate change impacts on marine life. The battery-powered “biomimics” hide among real mussels, with internal thermometers to estimate temperatures of their nearby living neighbors. Mussels’ body temperatures are changing with solar radiation, cloud cover and wind speed, says Brian Helmuth, a marine ecologist from Northeastern University in Boston. Because of this, the mussels’ body temperatures are generally much higher than the temperature of the surrounding air during exposure at low tide.

Downgrading the Great Dying

Wed, 18 Jan 2017 14:45:23 -0500

Estimates of species losses during six mass extinctions are lower when background extinctions are subtracted from previous estimates. Credit: Steven Stanley.

The end-Permian extinction, nicknamed the “Great Dying,” is thought to be the deadliest mass extinction in Earth’s history. Many textbooks claim that up to 96 percent of marine life died out during this event, but a new study suggests this cataclysmic number has been overestimated.

Fungi stabilize steep slopes

Wed, 18 Jan 2017 14:42:33 -0500

Researchers dug small terraces into the slope where rooted plants were placed. Credit: Alexander Bast.

The steep slopes of Switzerland’s high Alps are unstable — with loose soil and few plants — which poses hazards such as shallow landslides. In a new study, researchers have found that the symbiosis between plant roots and mycorrhizal fungi helps ground gravelly hillsides, suggesting a possible eco-engineering tool to stabilize the slopes.

Monkeys smash stone tool theories

Tue, 17 Jan 2017 14:19:02 -0500

Archaeologists have long credited stone flakes found at dig sites to tool-making hominins, but observations of wild capuchin monkeys in Brazil breaking stones may put an end to the assumption that all stone flakes were made by humans and their ancestors.

Comment: High school earth and space science should be taught by geoscientists

Tue, 17 Jan 2017 14:11:14 -0500

public domain.

A recent survey of U.S. science teachers’ understanding, perspectives and teaching of climate change — an important earth and space science (ESS) standard included in the new Next Generation Science Standards (NGSS) — revealed that teachers spend an average of only one to two hours per year teaching students about climate change. The survey study’s authors concluded that “[science] teachers may not be very knowledgeable about a wide range of evidence and how climate models work.” However, the authors did not distinguish between qualified ESS teachers and other teachers, like biology, physics or chemistry teachers who might be charged with teaching ESS topics. Other studies also noted that some teachers with biology degrees self-report not feeling prepared to teach climate change.

A new — and more toxic — normal? Harmful algal blooms find new habitats in changing oceans

Fri, 13 Jan 2017 13:06:09 -0500

An Envisat image of a phytoplankton bloom in the South Atlantic Ocean east of the Falkland Islands on Dec. 2, 2011. Chlorophyll pigment detected by ocean-color sensors on Earth-observing satellites can help identify species in algal blooms and their toxicity. Credit: ESA.

In May 2015, a seizure-wracked sea lion hauled itself ashore on a beach in southern Washington. Testing confirmed it was suffering from domoic acid poisoning, an illness that causes disorientation, seizures and sometimes death that stems from the consumption of fish or shellfish contaminated by a toxic species of algae called Pseudo-nitzschia. To the south, in warm California waters where localized toxic blooms of Pseudo-nitzschia are a near-annual occurrence, sea lion illnesses caused by exposure to domoic acid are common — however, this was a first in Washington. The sick sea lion was euthanized, but its stranding in Washington alerted coastal communities to the massive algae bloom that was engulfing coastal waters from Santa Barbara, Calif., all the way to British Columbia.

Geomedia: Music: The sounds of the sea

Tue, 27 Dec 2016 19:09:33 -0500

The Wave Organ is a collection of pipes on a San Francisco jetty. Credit: Frank Schulenburg, CC BY-SA 4.0.

At the ocean’s edge, the crash of waves against the shore is a familiar sound. It might be rhythmic, but it’s not particularly melodious. There are, however, a few spots around the world where the tides, waves and wind make actual music, thanks to acoustic man-made structures that use the movements of seawater to produce sound. Currently, three of these so-called tidal organs have been built, one each in Croatia, England and the United States.

Comment: Will we eliminate Earth's Ice-Age cycle?

Tue, 27 Dec 2016 18:58:28 -0500

Earth has gone through glacial-interglacial cycles for millions of years. Could humans be removing the glacial portion of that back and forth? Credit: Callan Bentley.

By Jacob Haqq-Misra

Down to Earth With: Paleoclimatologist Raymond S. Bradley

Tue, 27 Dec 2016 18:47:54 -0500

Bradley on one of his many trips to the Arctic. Credit: Raymond S. Bradley.

By Kate S. Zalzal

When 21-year-old Raymond S. Bradley left England in 1969 to pursue a graduate degree at the University of Colorado Boulder (CU), he thought he’d be studying Denver’s urban climate. But on arrival, a funding mix-up delayed the work and Bradley found himself in search of a new project. While his doctoral work would ultimately involve studying the precipitation history of the Rockies, a new opportunity came his way in the summer of 1970 when his officemate needed a field assistant for a trip to the Arctic. So, Bradley headed to Baffin Island in the Canadian Arctic on a three-month excursion that would prove to be just the first of dozens of Arctic expeditions to come over the course of a distinguished career.

Geologic Column: New Year's as we know it is new

Tue, 27 Dec 2016 18:25:51 -0500

Credit: Fran LoCascio

Cuneiform clay tablets discovered in Iraq reveal that more than 4,000 years ago, Babylonians were celebrating a New Year’s holiday. The Babylonian New Year, however, began with the first crescent moon after the spring equinox.

Busy as a bee: New species of bee quarries into sandstone

Tue, 27 Dec 2016 17:27:36 -0500

Michael Orr scales cliffs to investigate sandstone-boring bees. Credit: David Denlinger.

Researchers have discovered five nesting sites of a new species of bee (Anthophora pueblo) that prefers to make its home in sandstone. The newly discovered nests are located in natural formations as well as Ancestral Puebloan sandstone cliff dwellings in the southwestern U.S.

Supernova explosion detected in Early Pleistocene sediments

Tue, 27 Dec 2016 17:14:00 -0500

Multiwavelength X-ray, infrared, and optical compilation image of Kepler's supernova remnant, SN 1604. Credit: NASA.

When a massive star comes to the end of its life cycle, it goes out with a spectacular bang known as a supernova. Only three of these events have been observed in the Milky Way in the past 1,000 years. Evidence for older explosions can be detected in the form of rare elements found on Earth that are only produced by such explosions.

Earth's largest jet stream unexpectedly disrupted

Tue, 27 Dec 2016 16:59:15 -0500

The highly regular, quasi-biennial oscillation shifted unexpectedly in early 2016. Winds ordinarily flowing westward started flowing eastward, and moved lower in the atmosphere. Credit: ©JAMSTEC.

In early 2016, scientists first noticed an unexpected change in wind direction in the stratosphere some 25 kilometers above the equator. This shift signaled the beginning of a multimonth disruption of one of the most regular atmospheric phenomena known — the quasi-biennial oscillation (QBO). The disruption is the first such event observed in this system since record keeping began in the 1950s.

Current marine extinction unprecedented

Tue, 27 Dec 2016 16:41:59 -0500

Humpback whales in singing position. Credit: NOAA.

In today’s ocean, larger-bodied animals are more likely to become extinct than smaller creatures, according to a new study in Science. This is contrary to extinction patterns seen during other mass extinction events in Earth’s history, during which smaller species were hit the hardest.

Ant bodies shaped by environment

Tue, 27 Dec 2016 16:37:32 -0500

Environmental conditions such as temperature and UVB exposure help determine the coloration of ant species — dark or light— that predominate in an area. Credit: left: Shannon Hartman, www.antweb.org, CC BY 4.0; right: Will Ericson, www.antweb.org, CC BY 4.0.

Ants are ectotherms, which means their metabolisms are controlled by the temperature of their environment. New research shows that the environment also influences their color and size.

Getting there and getting around Shetland

Tue, 27 Dec 2016 15:02:22 -0500

Visitors to the Shetland Islands take overnight ferries, with comfortable berths and showers, from Aberdeen to Lerwick, the largest town in the Shetland Islands. The NorthLink Ferry has a children's playroom with toys and Viking costumes. Credit: clockwise from top: Swifant, CC BY-SA 2.0; Callan Bentley; Tom Bastin, CC BY 2.0.

Getting to the Shetland Islands requires taking a ferry from mainland Scotland. Ferries are very comfortable and well-run, with a smooth overnight passage from Aberdeen to Lerwick. We took that route up to Shetland, and a different route — to the Orkney Islands — on the way back. The schedule running from Lerwick to the town of Kirkwall (in Orkney) is less ideal, arriving in the middle of the night, but the local hotels are used to their guests dropping in at midnight.

Travels in Geology: Scotland's stunning Shetland

Tue, 27 Dec 2016 14:26:14 -0500

A typical view of the countryside of the Shetland Islands. Credit: Callan Bentley.

About 170 kilometers northeast of mainland Scotland, there is a remote cluster of islands featuring terrific geology, friendly people, an idiosyncratic landscape, and a great many sheep. This is Scotland’s Shetland Islands, an archipelago known to its friends as simply “Shetland.”

Panama's isthmus stays 3 million years young: Further evidence needed to support an older age

Tue, 20 Dec 2016 22:19:12 -0500

The formation of the Isthmus of Panama was a pivotal event for organisms on all sides of the narrow strip of land. Credit: K. Cantner, AGI.

The formation of the tiny Isthmus of Panama had major geographic repercussions, cutting off the Caribbean Sea from the Pacific Ocean and connecting North and South America. A new study using multiple lines of geological, biological and molecular evidence supports the most commonly accepted age of the isthmus, about 3 million years, refuting a pair of 2015 studies that placed the closing at a much earlier date.

Slow-moving slides may be triggered by cold temperatures

Tue, 20 Dec 2016 22:10:55 -0500

Landslides aren’t always fast-moving disasters. Slow landslides creep downhill at rates up to a few meters a year, which might not sound dramatic, but slow slides can still damage roads, pipelines and communities. Slow-moving slides are most commonly triggered by increased pore pressure in the soils due to rainfall or snowmelt, but in some places, according to a new study, temperature may also play a role. The new study looking at slow slides in Japan found that cold underground temperatures — independent of increased rainfall — may lubricate slow-moving slides.

Green corridors led humans out of Africa

Tue, 20 Dec 2016 22:02:31 -0500

Climate and vegetation changes over the past 120,000 years affected human dispersal out of Africa. Credit: K. Cantner, AGI, after Peter de Menocal and Chris Stringer, 2016

A trail of fossil, archaeological and genetic clues suggests that modern humans, who first evolved in East Africa about 200,000 years ago, may have made forays outside Africa via the eastern Mediterranean and the Arabian Peninsula as early as 120,000 years ago. But most fossil and archaeological evidence suggests they didn’t begin widely populating the rest of the world until about 60,000 years ago.

Mysterious Antarctic algae blown in by high winds

Tue, 20 Dec 2016 21:53:48 -0500

Melting of the East Antarctic Ice Sheet about 3 million years ago may have led to the wind-blown deposition of algae in the middle of the continent. Credit: Reed Scherer, Northern Illinois University.

When fossils of microscopic marine algae called diatoms were discovered high in the Transantarctic Mountains 30 years ago, the mysterious find set off a heated debate about whether Antarctica had thawed enough at some point within the last few million years for the emergence of algae-rich seas in the middle of the continent, or whether the diatoms were blown far inland by wind. Now, a new study links the two hypotheses: Researchers led by Reed Scherer of Northern Illinois University found that the algae were likely deposited by strong winds after substantial ice-sheet melt led to sea-level rise along eastern Antarctica.

Rethinking Pangea? Ancient ocean crust challenges supercontinent theory

Tue, 20 Dec 2016 21:19:32 -0500

Scientists deploy equipment to collect magnetic information about crust underlying the eastern Mediterranean Sea. Credit: Roi Granot.

The oldest piece of undisturbed oceanic crust ever discovered has been found beneath the eastern Mediterranean Sea, hidden under more than 10 kilometers of sediment. This ancient crust — estimated at up to 100 million years older than the oldest oceanic crust previously known — could reshape our view of global tectonics and the supercontinent cycle.

An undersea volcano yields its secrets

Mon, 19 Dec 2016 16:17:57 -0500

A hollow pillow flow with a frozen tongue of lava spilling from the opening rests atop glass-covered flows that formed during the 2015 eruption. The front of this flow was ~127 m thick. Water depth is 1773 m. Credit: University of Washington/OOI-NSF/CSSF-ROPOS

One of the world’s most active volcanoes has been seen by only a handful of humans — that’s because it lies 470 kilometers offshore of the Oregon-Washington border and about 1.5 kilometers below the surface of the Pacific Ocean. Nevertheless, Axial Seamount on the Juan de Fuca Ridge is one of the best studied of all volcanoes thanks to the Ocean Observatories Initiative (OOI), a global network of seven arrays consisting of more than 800 instruments.

Seafloor topography drives Earth's great conveyor belt

Thu, 15 Dec 2016 20:11:00 -0500

The Antarctic Circumpolar Current mostly runs free, connecting the Atlantic, Indian and Pacific ocean basins, but in one place it squeezes through a narrow, deep channel called the Drake Passage, where the topography affects the current. Credit: K. Cantner, AGI.

In the Southern Ocean, the world’s largest current in terms of volume transport — the Antarctic Circumpolar Current (ACC) — encircles Antarctica and connects the Atlantic, Indian and Pacific ocean basins, as it flows from west to east. The ACC influences ocean circulation and global climate, as it rises from the deep to interact with the atmosphere. In a new study, published in the Journal of Geophysical Research: Oceans, researchers have directly measured how seafloor topography affects the current’s structure — something that had only been theorized previously. Most of Earth’s oceans are bound by land on their eastern and western sides; the Southern Ocean is not. For the most part, the ACC runs free, but in one place, the entire ACC squeezes through a 1,000-kilometer-wide channel roughly 2,500 meters deep between the tip of South America and the Antarctic Peninsula, called the Drake Passage, home to a mountainous mid-ocean ridge.

Wintering in the high Arctic reveals surprising results

Wed, 14 Dec 2016 16:36:17 -0500

The Norwegian research vessel Lance wintered in the sea ice from January to June 2015. Credit: Monica Votvik/Norwegian Polar Institute

“Extremes define the Arctic.” With that observation, Mats Granskog of the Norwegian Polar Institute (NPI) began a tale of recent discoveries about change in the Arctic, resulting from and also causing climate change. Speaking to reporters in advance of scientific sessions at the American Geophysical Union’s fall meeting in San Francisco on Dec. 13, Granskog and colleagues described results of the Norwegian Young Sea ICE Expedition (N-ICE), a unique project that reached as far as 83 degrees north.

A story in the sediment: Emperor Yu's "Great Flood" may have been real

Wed, 07 Dec 2016 15:47:36 -0500

Fourteen skeletons of victims killed by an earthquake in Qinghai Province, China, some 4,000 years ago. The earthquake may also have triggered a landslide that blocked the Yellow River, eventually leading to a catastrophic outburst flood. Credit: Cai Linhai.

Ancient Chinese texts re-count the story of a great flood on the Yellow River some 4,000 years ago and Emperor Yu’s heroic efforts to dredge and redirect floodwaters, thereby taming the prolonged and catastrophic floodwaters and setting the stage for the agricultural boom that followed. His success is said to have proved a divine mandate for establishing the Xia dynasty, the first in China’s history. But in the absence of geological evidence for such a flood, scholars have long disagreed as to the veracity of the story.

Geologic Column: Conscious landscapes: Thinking like a septic tank

Wed, 07 Dec 2016 13:46:10 -0500

"He was mastered by the sheer surging of life, the tidal wave of being, the perfect joy of each separate muscle, joint, and sinew in that it was everything that was not death, that it was aglow and rampant, expressing itself in movement, flying exultantly under the stars…" - Jack London

Comment: To intervene or not to intervene: Improving the environment

Wed, 07 Dec 2016 13:42:32 -0500

Silviculture is the cultivation of trees. One approach to growing a healthy forest stand is to plant trees of varying ages and sizes, similar to this stand in Germany. Credit: Hans-Peter Ende.

We often view human civilization as an invader of the natural realm, displacing native species in favor of our own creations. Indeed, our technological prowess sometimes leads us to forget that we are biological creatures just like the rest of the world’s inhabitants. Yet we remain inseparable components of Earth’s system. Two competing philosophies provide guides for how we should tread on this planet: Aldo Leopold’s land ethic and John Locke’s land for human use idea. The environmental prescription of Leopold’s land ethic is that we should tread lightly and minimize our intervention. Locke’s philosophy, meanwhile, suggests land and resources are only as good as they are useful to us, such that we should use them freely and intervene as we see fit. But such attitudes may not be as much at odds as they appear, and each overlooks our ability to learn from mistakes of the past. Modern forestry practices — specifically silviculture, or the cultivation of trees — provide examples of the use of human ingenuity to enhance ecosystems, rather than disrupt them.

Down to Earth With: Underwater cave explorer Jill Heinerth

Wed, 30 Nov 2016 13:19:25 -0500

Jill Heinerth enters the cave at Devil's Eye Spring in Florida. Credit: Jill Heinerth, IntoThePlanet.com.

Jill Heinerth has trekked farther into caves than any woman in history, logging more than 7,000 dives across every continent and descending as far as roughly 140 meters underwater — recreational divers only reach depths down to 40 meters. She has dived inside icebergs in Antarctica, beneath the Sahara Desert, and in the turquoise waters of the Bahamas.

Getting there and getting around Patagonia

Tue, 29 Nov 2016 19:24:04 -0500

High-pressure systems that bring clear skies are reasonably common during the winter in Chilean Patagonia, a region that is notorious for its foul weather. Credit: Lon Abbott & Terri Cook.

Southern Chile has two main gateways, the homey town of Puerto Natales, a 1.5-hour drive from the national park, and Punta Arenas, a small city about 4 hours’ drive to the south. Of the two, Punta Arenas (PUQ) has the larger airport, which hosts regular year-round flights from Santiago on LATAM and Sky Airline, an efficient regional carrier, plus occasional flights from Puerto Montt in Chile’s beautiful Lake District. Flights to Puerto Natales (PNT) only operate during the summer season. There are no direct flights from the U.S. to this region.

Travels in Geology: Exploring an icon of Patagonia: Chile's Torres del Paine National Park

Tue, 29 Nov 2016 19:14:13 -0500

Mount Almirante Nieto and the Torres del Paine reflect in the still waters of Lake Amarga. Credit: Lon Abbott & Terri Cook.

While planning a family trip to Chile last year, Torres del Paine (pronounced “PIE nay”), a group of impossibly steep granite spires, was number one on our Chilean travel list. Despite their reputation for some of the foulest weather on earth, the peaks are magnets for tourists and rock climbers from around the world. But considering that reputation, the park’s location at 51 degrees south latitude and the fact that we were going during the Southern Hemisphere winter, we reluctantly crossed it off our list and concentrated on destinations in the country’s comparatively balmy north. That was until our teenage son Logan, an amateur mountain meteorologist, excitedly shared with us the results of his Patagonian climate research. “Dad, Dad!” he exclaimed. “High-pressure systems with clear weather are more common in the Patagonian winter than in summer, and winter temperatures seldom drop far below zero Celsius!” That report got Dad on board. Mom, who is not fond of the cold, was a harder sell, but sister Kailas’ enthusiasm sealed the deal. We’d soon purchased inexpensive off-season air tickets from Santiago to Punta Arenas and booked a room at Hosteria Pehoé, a lodge on Lake Pehoé, the location for the iconic photos of spectacular peaks that made the park famous. We were hoping that the investment would pay off with at least one fleeting glimpse of the mighty peaks through the notorious mist.

Geomedia: Gifts: Holiday Gift Guide

Tue, 22 Nov 2016 15:58:08 -0500

Geeky science gifts abound, but it’s not always easy to narrow down your choices. That’s especially true for the scientist — young or old — in your life who already seems to have their share of ordinary gifts. EARTH’s guide is your one-stop-shop for a range of unique and fun presents. This year’s guide even includes some crafts and kits for those who love to express science through art.

Ice (Re)Cap: December 2016

Tue, 15 Nov 2016 18:35:17 -0500

ASKY GPS station of the Greenland Global Positioning System Network. Research relying on this network shows the ground's movement on a regional scale. Credit: Michael Bevis.

Coral Reef Roundup: December 2016

Tue, 15 Nov 2016 18:20:04 -0500

Reefs that lack large predatory fish have 50 percent fewer nutrients. Credit: Nicodemo Lentile.

With multiple threats facing our coral reefs — from climate change to overfishing — and scientists continually studying the coral reefs beneath the waves, new findings are announced often. Here are a few of the latest updates.

Nutrient deficiency delayed life after mass extinction

Tue, 15 Nov 2016 18:16:07 -0500

Stephen Grasby collects samples from an outcrop on northern Ellesmere Island in the Canadian High Arctic. Credit: John Spear, Colorado School of Mines.

After Earth’s most severe mass extinction, life took up to 9 million years to recover — millions of years longer than after other extinction events. New research published in Geology suggests that a collapse in the ocean’s productivity might have been the cause.

Small-scale factors influence mantle flow under the seafloor

Tue, 15 Nov 2016 11:21:27 -0500

Deployment and recovery of an ocean-bottom seismometer (OBS) from the R/V Langseth in the Pacific Ocean more than 1,900 kilometers southeast of Hawaii. The OBS was lowered into the water via crane, where it then fell to the seafloor under its own weight. It stayed on the seafloor for 13 months; researchers then returned to the location, sent the instrument a message to disconnect from its anchor weight, and it rose to the surface where researchers scooped it up. Credit: both: James Gaherty.

In December 2011, scientists and technicians aboard the research vessel Marcus G. Langseth dropped several ocean-bottom seismometers into the deep Pacific more than 1,900 kilometers southeast of Hawaii to measure seismic activity and electrical conductivity to a depth of about 300 kilometers below the seafloor. Now, these measurements are providing new insights into how the mantle flows and deforms below the rigid tectonic plates that make up Earth’s surface.

Tilted Himalayan temples hold clues to past shaking

Tue, 15 Nov 2016 10:44:04 -0500

This leaning pillar at the Lakshi Narayan temple in Chamba, India, has been clamped to prevent further collapse. It may have been damaged during the 1555 earthquake. Credit: Mayank Joshi.

The Himalayan Mountains have not been raised gently. The ongoing collision between India and Asia that has uplifted the highest mountain range on Earth is punctuated by large earthquakes. But one region in the northwest Himalaya, known as the Kashmir seismic gap, has remained eerily quiet, save for a magnitude-7.8 event in 1905, and a mysterious quake in 1555. Now, a new study looking at damaged temples in the Chamba district of Himachal Pradesh in India, within the seismic gap, is shedding some light on the two historical quakes.

Cloud feedbacks drive climate sensitivity

Tue, 15 Nov 2016 10:41:04 -0500

Low tropical clouds seen from the International Space Station. Clouds like these reflect solar radiation back into space; without them, Earth's surface warms. Credit: NASA.

Fly over the tropical or subtropical oceans and you’ll see a white blanket of clouds covering the blue-green water. These low clouds, typically forming less than 2 to 3 kilometers above the ocean surface and covering up to 40 percent of Earth’s surface, play a critical role in the planet’s energy balance. Now, new research using satellite data and climate models to investigate how these clouds respond to climate change shows that they play a large role in regulating climate sensitivity.

Why tectonic plates lurch forward when they break

Tue, 15 Nov 2016 10:37:43 -0500

Like a rope tearing apart strand by strand, rifting perpetually weakens the lithosphere until it "snaps" and plate motions accelerate. Credit: S. Brune, 2016, CC BY-ND.

When continents rift, they often do so slowly at first, but then they can suddenly speed up. Why they suddenly go faster instead of rifting at a steady pace has long eluded explanation. But in a new study, researchers suggest that the lithosphere perpetually thins as it rifts, and that after passing a threshold, it snaps like a rope under too much tension, causing plate motions to accelerate.

Ancient plankton communities stressed before mass extinction

Tue, 15 Nov 2016 10:34:44 -0500

These fossilized shallow-water graptolites found in Nevada are from the Ordovician. Credit: Charles E. Mitchell.

Changes in our modern ecosystems, such as declines in biodiversity and invasive species, are similar to those that preceded the first of Earth’s mass extinctions about 443 million years ago, according to a new study. Researchers recently found that ancient plankton communities began to show environmental stress nearly 400,000 years before the extinction, as the planet cooled.

The path to gypsum is four steps long

Mon, 07 Nov 2016 14:34:53 -0500

Gypsum forms through a four-stage process, beginning with the formation of bits of nanocrystalline calcium sulfate that gradually assemble into larger aggregates, according to new research. Credit: James St. John, CC BY 2.0

Drywall and plasters made from both natural and manufactured gypsum are commonly used in home and building construction around the world, in part because of gypsum’s widespread availability. Despite its abundance, and its seemingly simple makeup, however, relatively little is known about how the calcium sulfate mineral forms in nature. In a recent study, researchers have shed new light on the multi-stage process by which gypsum grows — and the findings could help develop more efficient ways to manufacture the material.

Persistent Pacific warmth overshadows El Niño

Thu, 20 Oct 2016 10:37:53 -0400

Two ocean conditions — El Niño and a mass of warm water known as "the Blob" — both affected the Pacific last year but have faded away. Credit: Leslie Bell (lesliebell.com).

The El Niño of 2015–2016, dubbed a “super El Niño,” was officially declared over in May, bringing to a close one of the strongest El Niño events on record. Scientists are now unraveling the details of this climate phenomenon, and discovering how it interacted with other unusual ocean conditions to impact surface and subsurface ocean conditions within the California Current System (CCS) — one of the world’s major coastal upwelling zones and a region of great biologic productivity.

Frosted forams foil radiocarbon dating

Thu, 20 Oct 2016 10:35:33 -0400

Climate studies often rely on radiocarbon dating of tiny shells in seafloor sediments to pinpoint the timing of when warming or cooling events began and ended. But a new study indicates that chemical reactions that take place on the seafloor may affect the accuracy of such radiocarbon dates, with potential implications for the dates published by past studies.

Geologic Column: Digital divorce!

Thu, 20 Oct 2016 10:25:09 -0400

Credit: Kārlis Dambrāns, CC BY 2.0.

My desire to postpone mental aging by writing Geologic Columns for EARTH got me thinking about the impact of the digital revolution. Our compulsion for constant connection is troubling. A recent road trip to several western national parks with my device-addicted wife underscored the problem. Claudia was often an ethereal presence, compulsively uploading photos of Zion’s cliffs and the rim of the Grand Canyon. She lived in a separate world, emailing shots to friends and family. I was culpable too, agreeing to sneak away from our rim-side cabin, desperate for available Wi-Fi 5 kilometers away.

Comment: Understanding Earth in the wider sense of science

Thu, 20 Oct 2016 10:11:18 -0400

A view of most of North America taken from a low orbit of about 826 km altitude on January 4, 2012 from the VIIRS instrument aboard NASA's Earth-observing satellite - Suomi NPP. Credit: NASA, public domain.

“It isn’t easy being an organism. In the whole universe, as far as we yet know, there is only one place, an inconspicuous outpost of the Milky Way called Earth, that will sustain you, and even it can be pretty grudging,” Bill Bryson wrote in his 2003 tome, “A Short History of Nearly Everything.” This brilliant and humorous book is not about geology per se, but it is one of the best general science books I’ve read. Like many other scientists, I have read quite a few books about science written for the general public over the years and have kept my favorite ones. Recently, I browsed through these books, “A Short History” included, with this question in mind: How well are these general science books able to educate the public about Earth? And the short answer is, “Quite well.”

Down to Earth With: Volcanologist Kayla Iacovino

Thu, 20 Oct 2016 09:53:21 -0400

Kayla Iacovino stands on the crater rim of Mount Paektu Volcano in China, with a view of North Korea in the background and Lake Chon in the summit crater. Credit: Kayla Iacovino.

When Kayla Iacovino enrolled as a freshman at Arizona State University in 2005, she thought she might become an astronaut. But, after a field trip to outcrops in northern Arizona during her first semester, she became hooked on geology.

Toad behavior linked to climate change

Tue, 18 Oct 2016 13:39:12 -0400

Endangered Fowler's toads emerge in the spring earlier due to changing climate. Credit: David Green, McGill University.

Fowler’s toads — listed as endangered in Canada — hibernate for eight months to escape harsh winter conditions. They bury themselves up to a meter deep in the sand dunes along the shore of Lake Erie in Long Point, Ontario, which is the northern extent of their range. In May, they emerge at the surface to breed, in response to warmer air temperature and the lunar cycle. But scientists have now found that the toads are emerging earlier in the spring, according to a new study in Global Change Biology.

New magma chamber discovered beneath New Zealand

Tue, 18 Oct 2016 13:25:53 -0400

Subduction of the Pacific Plate under the North Island of New Zealand causes magma upwelling in the Taupo Volcanic Zone (TVZ). Credit: Ian Hamling.

New Zealand is no stranger to volcanism, but a newly discovered magma chamber 9.5 kilometers below the surface was an unexpected find for scientists studying ground movement around the country’s most active volcanic zone. The new chamber doesn’t sit directly beneath New Zealand’s familiar volcanoes, but just north and west of them beneath the Bay of Plenty coast. The find suggests recent intrusions of molten rock into a previously unknown magmatic zone. Researchers led by geophysicist Ian Hamling of GNS Science, a research institute and consulting firm in New Zealand, inferred the chamber’s presence indirectly from measurements of uplift in the Taupo Volcanic Zone (TVZ), which stretches beneath the country’s North Island to just offshore under the Bay of Plenty; the TVZ is where most of New Zealand’s volcanism over the past 1.6 million years has occurred. “The magnitude and spatial pattern of deformation along the Bay of Plenty coast are not consistent with a tectonic origin,” the authors wrote in a new study in Science Advances. “Given the proximity to the active TVZ, we assume that the observed uplift is a result of the accumulation of magma at depth.”

Cave dripwater records wildfires

Tue, 18 Oct 2016 13:13:11 -0400

The landscape above Yonderup Cave in Western Australia, after a wildfire. Credit: Pauline Treble.

Water seeps through soil and bedrock before dripping from the roof of a cave and carries with it elements of the outside world and its climate history. That is why speleothems, cave structures formed via precipitation, can be studied as climate proxies. New research suggests that the chemistry of the cave dripwater can also contain the signature of wildfires that burned outside the cave, on the ground above the cave’s roof, yielding a more complex picture of the past.

Electric fields lift dust into the air at massive scales

Mon, 17 Oct 2016 09:26:22 -0400

Francesca Esposito (third from right) and her research team measure dust and electric fields in the Sahara Desert. Credit: Francesca Esposito.

During the Dust Bowl of the 1930s, black blizzards of dust enveloped the Great Plains, destroying crops. When farmers heard a crackling sound over the radio, they often knew a dust storm was coming, as such storms carry an electric field that can disrupt electronic equipment. Scientists have known since the 1800s that these fields exist, but how they might affect the swirling dust around them has not been understood. In airborne dust over the Sahara Desert, scientists have now directly measured these electric fields for the first time and found that, if strong enough, the fields can lift vast amounts of dust into the air.

When Earth hit the reset button on life: New research on the Permian-Triassic mass extinction

Fri, 14 Oct 2016 13:04:19 -0400

The mountains at Van Keulenhamna in southern Spitsbergen, Svalbard, expose the Permian-Triassic boundary, which forms the main step in the cliff line (V-shaped notch in middle of page) where Permian cherts give way to Triassic shales. Credit: Paul Wignall.

About five years ago, paleobiologist Matthew Clapham was walking along Panther Beach on California’s coast when something caught his eye. He reached down, picked it up, and quickly became overjoyed. It was a living brachiopod: a marine animal similar to bivalves that are so rarely encountered in today’s oceans that Clapham, who studies the fossils of animals like brachiopods at the University of California, Santa Cruz, had never found a living specimen before that day, and he has not found one since.

Today's weather forecast: Good with a strong chance of improvement

Fri, 14 Oct 2016 09:45:52 -0400

The European Center for Medium-Range Weather Forecasts (ECMWF) produces operational analyses and predictions that describe the range of possible scenarios and their likelihood of occurrence, covering time frames ranging from medium range to monthly to seasonal. The arrows on the map correspond to wind speed and direction. Credit: ECMWF..

When people look to their phones, computers or TVs for weather forecasts, they want the forecasts to be accurate and timely. What goes into creating a forecast is rarely a concern, so long as it tells them whether to carry an umbrella or jacket that day, when to evacuate because a hurricane is coming, or when to prepare for a heat wave. It’s the job of the weather scientists, armed with computer models and an array of weather-observing instruments, to make accurate predictions. Yet, even with advancing technology, improving forecasts is challenging.

Ancient landslide gave us Zion Canyon

Wed, 28 Sep 2016 16:37:09 -0400

Zion Canyon in Utah's Zion National Park has a flat valley floor that was created when part of Sentinel Peak collapsed in a giant landslide, creating a dam and forming a lake that eventually filled in with sediment. Credit: courtesy of Sarah Meiser.

It took about 20 seconds for the Sentinel rock landslide to tumble into Zion Canyon, but those seconds changed the landscape for thousands of years.

Travel specs

Tue, 27 Sep 2016 09:52:23 -0400

Kilimanjaro's most recent volcanic activity occurred a couple hundred years ago, resulting in the creation of the Ash Pit within Kibo's central crater, Reusch Crater. Credit: Max Tuttman.

Booking a climb up Kilimanjaro can be a little daunting. I recommend first figuring out your climbing details and then figuring out how you will get to the mountain. Climbs are offered year round, but weather-wise, it is best to go in January and February or September and October. There are six main climbing routes up the mountain, and they all offer unique sites and spectacular views. Besides differing in scenery, these routes vary in physical difficulty, length (between five and 10 days), accommodations and prices. Prices range from $1,200 to $5,000 per person, with costs covering food, accommodations, park fees, transportation and rescue service, should it be necessary. Moreover, all of the agencies have their own supply of gear in case you are missing anything. For a list of respected, well-known tour operators, check out the “Climb with a Partner Company” page on the Kilimanjaro Porters Assistance Project Web site (www.kiliporters.org/index.php).

Celebrity climb

Tue, 27 Sep 2016 09:40:58 -0400

Located along the path to Mawenzi peak is Zebra Rock, a dark lava outcrop with white streaks of varying width formed from the leaching of overlying white calcium carbonate rocks. Credit: Zahra Hirji.

One billion people are without access to clean water today. When glacial deposits like the one atop Kilimanjaro melt away, that number will increase, some researchers say. To raise awareness about what some people are calling the global clean water crisis, a team of celebrities climbed Mount Kilimanjaro in January in the “Summit On The Summit.”

Travels in Geology: Climbing Mount Kilimanjaro: From parasitic cones to equatorial glaciers

Tue, 27 Sep 2016 09:34:47 -0400

Mount Kilimanjaro, located in northern Tanzania, is the tallest mountain in Africa, with an elevation of 5,892 meters above sea level. Credit: Max Tuttman.

Zahra Hirji

Travels in Geology: The Midwest's Little Egypt

Thu, 22 Sep 2016 10:25:30 -0400

Giant City, a collection of massive sandstone slabs, was deposited by an inland sea some 200 million years ago. Credit: Carol Unger.

Hiking trails wind through Giant City State Park, with evidence of 200-million- year-old inland seas and thousands of years of glacial scouring and water erosion. Credit: AGI.

Lots of people may be delaying the family vacation this year, waiting for rosier economic times. Road trips, however, might still be in the budget. And when it comes to choosing a destination, geology enthusiasts should give serious consideration to the Shawnee National Forest in southern Illinois. The forest is an easy half-day’s journey or less from a number of cities, including Chicago, St. Louis, Nashville, Memphis, Louisville, Indianapolis and Cincinnati — perfect for a weekend getaway or perhaps a longer backpacking expedition.

Travels in Geology: Gubbio, Italy: A geologist's mecca

Wed, 21 Sep 2016 10:09:14 -0400

Credit: Kathleen Cantner, AGI ; globe: AGI /NASA.

The Apennines are often called the backbone of Italy. Credit: Terri Cook and Lon Abbott.

The history of our planet is written in the rocks. It was in Italy where the earliest geologists first understood this. As a geologist planning a trip to Italy last summer, I wanted to visit many of the country’s famous geoattractions, including Pompeii, Mount Etna and Tuscany’s rolling green hills. And at the top of my travel list was the small medieval hill town of Gubbio, located in the beautiful Apennine Mountains in central Italy’s Umbria region. Here, studies of the limestone layers just outside the town’s encircling walls produced one of the great geological discoveries of the 20th century: evidence that a 10-kilometer-wide bolide smashed into Earth 65.5 million years ago at the end of the Cretaceous period, extinguishing half the life forms on the planet and finishing off the dinosaurs.

Ice (Re)Cap: October 2016

Wed, 21 Sep 2016 08:18:53 -0400

At glaciers and snowfields around the Arctic, researchers sampled snow tinted by red algae, which bloom in spring and summer and contribute to lowering surface albedo. Credit: Liane G. Benning, GFZ.

Water use soared as workers flocked to North Dakota's oilfields

Tue, 20 Sep 2016 15:13:27 -0400

Pump trucks transport water from Lake Sakakawea in North Dakota's Bakken region to oil well production sites. Credit: Rob Horner.

Amid North Dakota’s oil boom, about 24,000 temporary oilfield workers moved to Williams County — in the state’s Bakken oil shale region — between 2010 and 2012, almost doubling the area’s population. In a new study, researchers found that those workers have been responsible for the region’s skyrocketing water use almost as much as hydraulic fracturing by the oil industry itself.

Geologic Column: Proposing a new U.S. Holiday: Explorers' Day

Tue, 20 Sep 2016 14:15:05 -0400

Seattle's Leif Erikson memorial statue. Credit: Steven Pavlov, CC BY-SA 3.0.

October has two holidays, just days apart, that celebrate two individuals both heralded as the discoverers of the New World: Leif Erikson and Christopher Columbus. Why do most of us celebrate Columbus Day but not Leif Erikson Day?

Comment: Did life start on a snowball?

Tue, 20 Sep 2016 13:53:15 -0400

Conventional wisdom suggests that life on Earth emerged on a hothouse, but what if it instead emerged during a Snowball Earth? Credit: Callan Bentley.

The Hadean Eon, the first 500 million years of Earth’s history, was a harsh and violent time. After Earth formed 4.6 billion years ago, the leftover debris in the solar system bombarded Earth’s surface. It is thought that the moon formed during this turbulent period, coalescing out of the dust from a collision between Earth and a larger planetoid, perhaps the size of Mars. Earth’s molten surface was beginning to take shape during this period, and the onset of volcanism helped develop the atmosphere. Geologic evidence suggests temperatures were smoking hot. Somewhere toward the end of the hell-like Hadean, and the more quiescent Archean Eon that followed, life emerged on Earth. But what if life emerged not during a hothouse, but instead during a global icehouse — a Snowball Earth?

Benchmarks: October 2, 1574: Dutch unleash the ocean as a weapon of war

Tue, 20 Sep 2016 13:28:47 -0400

Storm clouds over Leiden, Holland, in 2009. Another storm over the Netherlands, nearly four and a half centuries earlier, helped relieve the city from a Spanish siege. Credit: Daan M, CC BY-SA 2.0.

During the siege of Leiden, Prince William of Orange, leader of the Dutch War of Independence, broke the dikes on the River Maas, allowing the North Sea to flood the countryside to drive the Spanish invaders out. This portrait of him was painted by Adriaen Thomasz Key about five years before the prince was assassinated in 1584. Credit: Rijksmuseum, Amsterdam.

Lucas Joel

Geomedia: Books: "Alfred Wegener": The definitive biography of a geoscience star

Tue, 20 Sep 2016 12:30:04 -0400

"Alfred Wegener: Science, Exploration and the Theory of Continental Drift," by Mott T. Greene, Johns Hopkins University Press, 2015, ISBN 9781421417127.

Today, Alfred Wegener’s name appears in almost every geology textbook. He is celebrated as the father of the continental drift hypothesis, the forerunner of plate tectonics. This recognition is rather recent — since about the early 1970s, when plate tectonics became a unifying theory to explain the origins of continents, oceans, mountains, volcanism and many other geologic processes. During his life, Wegener’s hypothesis was rejected by many geologists, more so in North America than in Europe. The dramatic change of his status from heretic to hero thus makes Wegener’s story even more fascinating, not only to earth scientists but to general readers as well.

Getting there and getting around Guatemala's Volcan Pacaya

Thu, 15 Sep 2016 14:11:12 -0400

Shops, restaurants and hotels line Antigua's famed cobblestone streets. Agua Volcano looms behind Santa Catalina Arch, which originally allowed nuns to cross from one side of the Santa Catalina convent to the other without going outside. Credit: ©iStockphoto.com/ loca4motion.

Visitors to Guatemala fly into Guatemala City’s La Aurora International Airport, the country’s only international airport. From there, I recommend traveling to the beautiful old colonial city of Antigua, a UNESCO World Heritage site that offers some of the best of Guatemalan culture, from restaurants and bars to architecture and shopping. It is common for travelers to share a shuttle bus from the airport to Antigua — expect to pay about $10 for the 60- to 90-minute journey.

Travels in Geology: Guatemala's Volcan Pacaya: A feast for the senses

Thu, 15 Sep 2016 14:00:06 -0400

The summit of Volcán Pacaya in February 2016. Credit: Michael Steel.

Located in northernmost Central America, Guatemala is home to 22 volcanoes, seven of them active, some of which are accessible to hikers looking for a thrilling experience. The most popular volcano for tourists to climb is the infamous Volcán Pacaya, close to the former capital city of Antigua — a UNESCO World Heritage site that is worth a visit in its own right. The trip up Pacaya is suitable for hikers of all levels, including beginners and youngsters, as it takes just a few hours to complete. The views en route and at the summit are spectacular; and how many other places are there where you can stand atop still-cooling tephra while roasting marshmallows over “hot pockets” in the ground? If climbing an active volcano is on your bucket list, I highly recommend Pacaya.

Clouds can form without particles

Tue, 13 Sep 2016 14:25:29 -0400

Federico Bianchi and his colleagues analyzed air samples at Jungfraujoch Research Station in the Swiss Alps to study the formation of cloud condensation nuclei from organic compounds in the troposphere. Credit: Federico Bianchi.

In addition to their aesthetic and photogenic appeal, clouds play a crucial role in Earth’s climate and ecosystems, helping regulate temperatures by reflecting sunlight. All clouds — from fluffy cumulus to wispy cirrus — grow from seeds that, more often than not, are tiny particles of pollen, dust or chemical aerosols that float into the atmosphere from Earth’s surface. Sulfuric acid, a byproduct of volcanic eruptions and fossil fuel combustion, is one of the most ubiquitous precursors to atmospheric aerosols today and has long been thought to play a major role in modern cloud formation. But what about earlier in Earth’s history, before humans impacted the atmosphere as much? Three new studies, representing both experimental and field data, suggest that the planet’s plants and trees might have done just fine on their own pumping cloud-forming aerosols into the skies.

Tectonic rejuvenation in North America's ancient mountains

Tue, 13 Sep 2016 14:21:44 -0400

New Hampshire's Mount Washington, snowcapped in winter, is a part of the White Mountains in the northeastern United States. Credit: Library of Congress.

The mountains of eastern North America, like the Appalachians, Adirondacks and White Mountains, are old: They grew as the pieces of the supercontinent Pangea collided and assembled more than 300 million years ago. It’s been long thought that, after forming — and subsequently undergoing additional uplift and deformation due to rifting during the opening of the Atlantic Ocean — the mountains fell dormant between about 160 million and 200 million years ago. But new work is adding to a growing body of evidence suggesting the ranges were tectonically active well after that.

California drought stops slow-moving landslides

Tue, 13 Sep 2016 14:15:34 -0400

The Eel River Basin is home to hundreds of slow-moving landslides, some of which have all but stopped because of California's ongoing drought. Credit: Georgina Bennett.

Most people think of landslides as fast-moving events, but many slides creep slowly, advancing over hundreds or thousands of years. In a new study, researchers looking at creeping landslides in California have revealed an unexpected consequence of the state’s ongoing drought: Many of the slides have nearly stopped due to the lack of water in the soil.

Early Earth's atmosphere weighed half as much

Tue, 13 Sep 2016 14:05:12 -0400

Researchers analyzed lava flows on the banks of Australia's Beasley River. Gas bubbles that formed as the lava cooled, 2.7 billion years ago, have since filled with calcite and other minerals and appear as white spots. Credit: Sanjoy Som/University of Washington.

The conditions that prevailed on early Earth are, in many ways, as alien as those found on far off exoplanets. Some clues can be found in ancient rocks, but our understanding of the first few billion years of our planet’s history remains hazy. In a new study, a team reports evidence in 2.7-billion-year-old basalt that young Earth’s atmosphere was just half as heavy as today, an insight that may shed light on how marginal conditions found on exoplanets could still support life.

Junk gem reveals new diamond-forming process

Tue, 13 Sep 2016 13:52:24 -0400

Researchers found a thin magnetite corona — the dappled band shown in (a) and with individual grains colored in (b) — around a sulfide inclusion in a diamond from Botswana, evidence of a diamond-forming process called redox freezing. Scale bars are 0.5 micrometers. Credit: Jacob et al., Nature Communications, June 2016, CC BY 4.0.

Not all diamonds are gems. Those found bearing imperfections or inclusions, known as bort or junk diamonds, are often demoted to industrial uses such as in diamond-tipped drill bits. They also sometimes find their way to scientists interested in using the inclusions to study how such stones form. Now, a team studying a junk diamond from Botswana with a large black sulfide inclusion has uncovered evidence of a previously unrecognized diamond formation process that occurs in the deep mantle.

Bad weather hampered Mongol invasion of Europe

Tue, 13 Sep 2016 13:25:32 -0400

Tree rings helped researchers piece together a new hypothesis as to why the Mongol army withdrew from western Hungary in 1242. Credit: Ulf Büntgen.

In 1241, the armies of the Mongol Empire, continuing their campaign through Asia and Europe, invaded western Hungary. Before long, however, the Mongols withdrew their forces, beating a sudden retreat that has long baffled historians. Now, drawing on high-resolution climate data from tree rings, researchers may have found a clue as to why: It seems wet weather created adverse conditions for the Mongol army, eventually forcing it to retreat from what was to become historically its westernmost advance.

Thirsty business: How the tech industry is bracing for a water-scarce future

Tue, 13 Sep 2016 09:37:37 -0400

Servers at the Facebook data center in Prineville, Ore., one of the world's most environmentally friendly data centers, use 70 percent less water than Facebook's other data centers. Credit: Facebook, Inc.

Prineville is a sleepy town nestled in the sagebrush desert between the snowy peaks of Cascade volcanoes and the rumpled hills of the Ochoco Mountains. Stunted juniper and shaggy shrubs dot the flat-topped hills that rise above the community of 9,000 people in central Oregon. A narrow ribbon of green — the Crooked River Valley — winds through the parched, buff-colored landscape. It’s striking, but not an obvious place to escape a drought.

Exploring the newest gift to America: Katahdin Woods and Waters National Monument

Mon, 29 Aug 2016 18:01:08 -0400

“Are you sure this is right? It feels like we are headed to Neverland,” my boyfriend asked me while hiking last weekend. We were in the country’s newest national monument — Katahdin Woods and Waters National Monument — a remote area of about 35,400 hectares in north-central Maine, designated by President Obama under executive authority last Wednesday, one day before the 100th anniversary of the National Park Service.

Benchmarks: October 1, 1960: Camp Century, a cold war ice fortress is built

Tue, 23 Aug 2016 13:51:59 -0400

The soldiers who staffed Camp Century enjoyed many of the same accommodations as their fellow soldiers at bases around the world. They had a mess hall, a chapel, a theater, a dispensary, an emergency room and even a hobby shop, all onsite. Just like their counterparts elsewhere, Camp Century’s soldiers got out of bed, shaved, showered and went to work. However, when Camp Century personnel opened the door and walked from their quarters, they saw only one thing: snow. No sun, no moon, no sky, and no distant horizon. Just a corridor with walls, floor and ceiling made of snow.

Benchmarks: September 23, 1933: The U.S. oil industry arrives in Saudi Arabia

Tue, 23 Aug 2016 10:57:38 -0400

The towns of Jubail and Dammam on Saudi Arabia's Persian Gulf coast played major roles in the early history of oil exploration in the country. Credit: ©NormanEinstein, Creative Commons Attribution-ShareAlike 3.0 Unported.

Saudi Arabia currently produces about 11 million barrels of oil per day, edging out Russia and the U.S. to rank first in the world in production, according to the U.S. Energy Information Administration. The desert kingdom also has proven reserves of more than 260 billion barrels — spread among numerous fields (though most reside in a handful of giant fields) — amounting to about one-fifth of the world’s total. The country exports more oil than any other and exerts an undeniably prominent influence on the world oil market from its seat in the Organization of the Petroleum Exporting Countries (OPEC).

Benchmarks: August 24, 1873: The Mount of the Holy Cross is found, photographed and mapped

Tue, 23 Aug 2016 10:42:22 -0400

The Mount of the Holy Cross in Colorado, as photographed by William Henry Jackson in 1873. Credit: USGS Photographic Library.

The rumors had persisted for decades, some said for centuries. Deep in the Colorado Rockies was a mystical mountain. Upon the face of a towering peak rose a massive cross, formed by snow accumulating in two huge cracks. In his 1868 book, “The Parks and Mountains of Colorado: A Summer Vacation in the Switzerland of America,” journalist Samuel Bowles wrote, “It is as if God has set His sign, His seal, His promise there — a beacon upon the very center and hight [sic] of the continent to all its people and all its generations.”

Travels in Geology: Limestone and legends in Northern Vietnam

Fri, 19 Aug 2016 15:33:30 -0400

The so-called jade islands of Ha Long Bay in Northern Vietnam are the embodiment of karst topography. More than 1,600 islands pierce the emerald-green water. Credit: ©iStockphoto.com/Nikada.

Early in Vietnam’s history, the country was repeatedly attacked by enemies arriving by sea. According to Vietnamese legend, the mythical Jade Emperor, who felt sorry for the Vietnamese people, sent the Mother Dragon and her children to Earth to help them defend their land. When enemy ships next approached, the dragons descended from the sky and spat countless giant pearls into the ocean. These magically turned into a multitude of jade islands, which linked together to create an invincible barrier that barred the approaching ships and caused them to crash and sink beneath the waves. Following the battle, the Mother Dragon and her children were so enthralled by the bay’s beauty that they decided to remain on Earth rather than return to heaven. To remember the dragons’ help, the local people named one bay Ha Long, which means “descending dragon,” and a bay to the northeast, where her children descended, Bai Tu Long, which means “thanks to the Dragon’s children.”

Down to Earth With: Hydrogeologist Shemin Ge

Fri, 19 Aug 2016 14:51:51 -0400

Shemin Ge is a hydrogeologist at the University of Colorado Boulder and GSA's 2016 Birdsall-Dreiss Lecturer. Credit: Connie Ge.

" graduated from high school in China, the country was still in the throes of the Cultural Revolution. During this movement, which lasted from 1966 to 1976, many colleges and universities were closed, and Ge, like most teenagers from urban areas, was sent to work in the countryside. She was assigned to a brick-making factory, where she had to haul heavy, machine-molded bricks outside so they would dry in the sun. Unless the forecast called for good weather, the teens also had to cover the bricks each evening to prevent them from cracking in the rain.

Geologic Column: The notion of mantle plumes

Fri, 19 Aug 2016 14:37:13 -0400

The dome fountain shown here is about 20 meters (66 ft) tall and formed during the 1969-71 Mauna Ulu eruption of Kilauea Volcano, Hawai`i. Credit: public domain.

The article “The Question of Mantle Plumes” in the January/February 2016 issue of EARTH was a well-researched and educational reminder that the mantle plume model is far from established as an accurate depiction of circulation in the mantle. It reminded me of my personal, evolving trip along the plate tectonic road.

Comment: Mudrock cement and the importance of basic research

Wed, 17 Aug 2016 13:58:32 -0400

Red mudrock in the Ragged Reef Formation ( Pennsylvanian), Cumberland Basin, Nova Scotia. Credit: Michael C. Rygel, CC BY-SA 3.0.

Diverse motivations drive scientific research. For many of my geoscience colleagues, curiosity seems motivation enough. However, motivations beyond mere curiosity often spur the funding of science. Geoscience offers many questions of such immediate and practical value that much funding is supplied by private industry, although work of a more basic nature may also be funded publicly by governments at many levels. In the political world, it’s often argued that responsibility for advancing science should be weighted more heavily on one sector or another. But it need not be imbalanced: What often gets lost in such conversations is that science truly needs the fullest possible portfolio of motivations — and funders — to be most effective.

The current extinction of life will leave a scant fossil record

Wed, 17 Aug 2016 13:18:15 -0400

In this artist's illustration, a modern coyote examines the skull of a dead Pleistocene ancestor from the Rancho La Brea Tar Pits. Credit: Doyle V. Trankina (artist).

Life on Earth has endured five major mass extinctions, known as the “Big Five.” We know about these past events thanks to fossils: During mass extinctions, many species evident in the rock record disappeared from Earth relatively quickly. Today, human alteration of the environment is driving what scientists call the sixth great extinction, but according to new research, the current extinction differs from the Big Five in a key way: Much of the life facing extermination today will likely not be preserved as fossils. This means that, to future paleontologists looking at the rock record from today, the sixth extinction might not appear to have been such a major event.

Observers at the edge of the ice: Smaller, cheaper machines can safely go where humans can't

Wed, 17 Aug 2016 10:23:05 -0400

Tourists and glaciologists alike want to get as close to glaciers as is safely possible. Credit: Gary Bembridge, CC BY 2.0 Credit: Gary Bembridge, CC BY 2.0.

Any tourist bound for Greenland or Alaska on a cruise ship would be happy to capture video of a huge chunk of ice as it calves from the face of a glacier hundreds of meters tall or more — filmed from a safe distance of course. When it hits the ocean below, falling ice can send up cascading walls of water that could capsize or drown any vessel that dares too close.

Zircons hold clues to early Earth

Tue, 16 Aug 2016 16:46:03 -0400

Shatter cones produced in local rock by the shock wave of the Sudbury impact 1.85 billion years ago. Credit: Gavin Kenny, Trinity College Dublin.

Not much is known about the first 500 million years of Earth’s history, between 4.5 billion and 4 billion years ago. We know the interior of the planet was hotter than it is today, and that Earth’s surface experienced intense meteorite bombardment, which left the surface pocked with magma-filled craters. But with no rock record available from this period — the oldest rocks are 4.04 billion years old — scientists must look to the composition of tiny grains of the mineral zircon to provide clues about Earth during the Hadean Eon. But where did the zircons come from?

Tiny ocean bacteria could play big role in climate

Tue, 16 Aug 2016 16:36:11 -0400

Stephen Giovannoni's team samples for Pelagibacterales off Bermuda. Credit: Ben Temperton.

In the 1990s, researchers identified the most abundant group of organisms in the ocean as Pelagibacterales, a class of free-living bacteria that live in surface waters as a microscopic but major part of the phytoplankton community. Now, a new study suggests that Pelagibacterales could play an important role in the global climate cycle by producing dimethylsulfide (DMS), an organosulfur compound that stimulates cloud formation when it gets into the atmosphere.

Earthworms build big mounds to escape floodwaters

Tue, 16 Aug 2016 13:51:12 -0400

Large mounds, called surales, dot the landscape in the Orinoco Llanos region of South America. Credit: Delphine Renard.

When researchers looking for archaeological remains in satellite imagery came across unidentified mounds — some as tall as humans — in the seasonally flooded wetlands of northern South America, they found a landscape shaped not by ancient civilizations but, rather, by modern earthworms.

Bubble accumulation could explain massive volcanic sulfur releases

Tue, 16 Aug 2016 13:35:13 -0400

Steam and gas rise from the caldera floor of Mount Tambora in Indonesia. New research may explain why some volcanic eruptions, such as Tambora's 1815 eruption, are so explosive and emit large amounts of sulfur gases. Credit: Georesearch Volcanedo Germany, CC BY-SA 3.0.

The spectacular 1815 eruption of Indonesia’s Mount Tambora spewed large amounts of sulfur gases into the atmosphere, which formed fine sulfur-rich particles that blocked sunlight and lowered global temperatures by more than half a degree Celsius, causing famine and death on a global scale.

Mantle convection makes Earth's crust bob

Tue, 16 Aug 2016 13:24:06 -0400

Coral reefs at Cap Miné near the northern end of Madagascar attest to uplift in the area caused by underlying mantle upwelling: While a living reef forms underwater today, the remnants of two former reefs — one upon which the lighthouse sits and one capping the hill at left — were raised out of the water. Credit: Mark Hoggard.

From the earthquake-prone Himalayas and Andes to the volcanically active “Ring of Fire” around the Pacific, the boundaries of Earth’s tectonic plates are often sites of considerable geologic activity. In contrast, the interiors of tectonic plates have been thought to be relatively rigid and quiet.

Benchmarks: July 1, 1912: Hawaiian Volcano Observatory officially becomes the first of its kind in U.S.

Mon, 01 Aug 2016 13:58:35 -0400

Thomas A. Jaggar Jr., seen here in 1916, prompted the establishment of the Hawaiian Volcano Observatory and served as its director from 1912 until 1940. Credit: USGS HVO.

Living on the fringe of an active volcano in Hawaii is a precarious venture. Because Hawaii’s shield volcanoes aren’t prone to explosive activity, you’re typically not threatened by violent eruptions such as would occur at Mount St. Helens, for example. On the other hand, the slow-moving, unpredictable lava flows can still overtake your home, even if it has avoided years of previous eruptions.

Geomedia: Film: A glimpse into the geology of 'Star Trek Beyond'

Thu, 28 Jul 2016 18:55:57 -0400

[Spoiler Alert: This review reveals key plot points of the movie.]

'Star Trek Beyond' is the third installment of the latest series of 'Star Trek' movies. Credit: courtesy of Paramount Pictures

After a three-year wait by anxious fans, “Star Trek Beyond” hit theaters nationwide July 22. The third installment of the latest series of “Star Trek” movies, directed by Justin Lin and co-written by Simon Pegg, features more than two hours of action, stunning scenery and witty banter among the USS Enterprise crew — plus a bit of geology.

Ice (Re)Cap: August 2016

Tue, 26 Jul 2016 10:03:18 -0400

Landsat data collected between 1984 and 2012 show that much of Canada and Alaska is greening as vegetation expands. Credit: NASA Goddard Space Flight Center/Cindy Starr.

Mauna Loa's mysterious Ninole Hills were once a rift

Tue, 26 Jul 2016 09:57:04 -0400

The Nīnole Hills (orange area) on the southeast flank of Mauna Loa are suggested to be a failed rift (blue dashed line) that migrated toward the current Southwest Rift Zone (yellow dashed line). Credit: U.S. Geological Survey.

Hawaii’s Nīnole Hills, jutting out from Mauna Loa’s southeast flank, are one of the most striking features on the Big Island, though their geologic origins have long been a mystery. A new study looking at gravity anomalies under the hills is revealing that the hills are part of an older rift system that predates the currently active Southwest Rift Zone. The seemingly sudden switch from one rift system to another may provide some clues as to how Mauna Loa grew to be the largest volcano on Earth. “A lot of different ideas have been proposed to explain how the Nīnole Hills were created,” says Jeff Zurek, a geophysicist at Simon Fraser University in Burnaby, British Columbia, and lead author of the new study published in Geophysical Research Letters. It’s been suggested that the hills could be the remnants of an older summit of Mauna Loa, or its predecessor, Mohokea, or that faulting and landslides could have created the unusual topography of the hills, or that they could be from an older, inactive rift system.

Benchmarks: August 25, 1916: The National Park Service is established

Tue, 26 Jul 2016 09:37:04 -0400

Yosemite Valley with Half Dome in the background. Although Yellowstone was the first national park, the idea of national parks can be traced to the federal government's 1864 decision to grant care of Yosemite to the state of California. Credit: AngMoKio, CC BY-SA 2.5.

The U.S. national parks are sanctuaries where one can find refuge in nature and marvel at its grandeur — from the glacially sculpted granitic monoliths of California’s Yosemite to the watery wilderness of Florida’s Everglades. This August, the agency that works to ensure the parks’ preservation for future generations, the National Park Service (NPS), celebrates its 100th anniversary.

Geologic Column: Editia elegantis: A story of science, discovery and the elegance of a wife's contribution

Tue, 26 Jul 2016 09:24:12 -0400

Roger and Edith Brayer in the mid-20th century. Credit: courtesy of Patrick C. Brayer.

The account of how the crustacean Editia elegantis was discovered has been the source of dinner party amusement for my family and friends since I was a child. The lore surrounding this find is not a tale of a paleontologist traveling the planet to exotic locations, but rather a story of disagreement between a young wife and her graduate student husband set in a small kitchen in a tiny St. Louis apartment in the late 1940s or early 1950s. People are often surprised to hear that a simple disagreement between my father and mother resulted in an article in the Journal of Paleontology and a collection in the Smithsonian National Museum of Natural History. Such lofty results all depended on someone with no scientific training uttering the words: “That’s not sand!”

Geomedia: Books: 'FORE' helps you project the future, with a laugh

Tue, 26 Jul 2016 09:16:44 -0400

"FORE and the Future of Practically Everything," by R. L. Handy, Moonshine Cove Publishing, LLC, 2013, ISBN-13: 978-1937327316.

What if we could project the future of nearly everything with a single type of mathematical equation? In “FORE and the Future of Practically Everything,” a book replete with humor and keen insight, retired civil and geotechnical engineer Richard L. Handy valiantly attempts to demonstrate the projective power of mathematics by exploring an eclectic assortment of examples.

Down to Earth With: National Park Service Geologic Resources Division chief David Steensen

Mon, 25 Jul 2016 14:58:14 -0400

David Steensen is chief geologist of the National Park Service. Credit: courtesy of David Steensen.

" in 1986, he did not think he’d be working for the National Park Service for more than a few years. He had been hired into a four-year fixed-term position to help restore the local watershed from the destabilizing effects of logging that occurred prior to the park’s establishment, and he knew that the park service rarely hired geologists into permanent positions.

Teaching geology to biologists: An essay on an interdisciplinary field trip in Africa

Mon, 25 Jul 2016 14:21:50 -0400

Jill Peterson, an Adams State student on the trip, painted this representation of the field trip. Credit: Jill Peterson.

We stop next to a wide, dry, creek bed on the floor of a steep canyon near Tarangire National Park in northern Tanzania. Elephants spray water on themselves and their companions. In the tall baobab trees on the far side of the valley, monkeys jump from limb to limb and tree to tree, over the heads of impalas that don’t seem to care. I am standing in the back of one of our open-top Land Rovers and, like the monkeys, I’m waving my arms this way and that as I discuss the geologic strata in the canyon walls. Like the impalas, the khaki-clad college students in the Land Rovers don’t seem to notice.

Researchers profile magma chamber beneath North Korean volcano

Wed, 20 Jul 2016 14:00:29 -0400

Lake Chon fills part of Mount Paektu's caldera on the border of China and North Korea. Credit: James Hammond.

An enigmatic volcano straddling the border between North Korea and China has been investigated for the first time by an international team of seismologists. In 2013, researchers installed seismometers near the volcano — called Mount Paektu in North Korea and Changbaishan in China — to determine what was going on beneath the surface. The team’s results, detailed in a new study published in Science Advances, reveal a potential source of magma that may have created one of the largest volcanic eruptions in the last few thousand years — and that could cause the volcano to erupt again.

Volcanoes and historical politics

Tue, 19 Jul 2016 10:35:32 -0400

As well as influencing art and faith, volcanoes are often portrayed as the very manifestation of the human condition. Expressions of anger are readily described as “volcanic.” They have become a metaphor for anything of suitable magnitude or wrath. One such painting sees a volcano become the embodiment of the French Revolution.

Getting there and getting around Zermatt

Tue, 19 Jul 2016 10:27:36 -0400

Zermatt, a car-free resort town at the foot of the Matterhorn, can be reached from major international airports in Geneva, Zürich or Milan. All three airports offer nonstop flights from several North American cities and have numerous rental-car agencies. Switzerland has four official languages, of which German and French are the most commonly used, but road signs are easily followed by English speakers, making it easy to navigate around the country. However, private cars are not allowed in Zermatt, so you might instead want to take one of the Swiss Rail Network’s clean and reliable trains to Zermatt, a 3.5-hour trip from Zürich or a four-hour trip from Geneva. If you do drive, you must park in a garage in Täsch, 5 kilometers north of the resort town, and take a train or taxi into town. The village itself is quite walkable; a 10-minute stroll will get you across town.

Drilling for gold inside a submarine volcano

Thu, 14 Jul 2016 15:12:35 -0400

In 2018, researchers aboard International Ocean Discovery Program's JOIDES Resolution ship will drill into an active submarine volcano — Brothers Volcano, part of the Kermadec Arc north of New Zealand — for the first time. Credit: William Crawford, IODP JRSO/TAMU

Earth scientists have been given the green light to drill into an active submarine volcano for the first time, with the hope of discovering substantial new reserves of valuable metals, as well as new forms of extreme life.

Snake River eruption history offers glimpse into Yellowstone hot spot dynamics

Thu, 14 Jul 2016 13:44:08 -0400

In the Cassia Hills in southern Idaho, researchers found evidence of a dozen large eruptions from the Yellowstone hot spot volcanic system that occurred between about 11.3 million and 8 million years ago. Credit: Knott et al., GSA Bulletin, March 2016.

About 8 million years ago, what is now the Snake River Plain of southern Idaho ripped open in a catastrophic super-eruption that spewed roughly 1,900 cubic kilometers of lava and ash across thousands of square kilometers. New research, based on field studies and geochemical analyses of rocks collected on the plain, shows that this eruption was just one of many massive mid-Miocene volcanic events arising from the Yellowstone hot spot. The work also provides a window into the complex and evolving mantle-crust interactions that have occurred as the North American Plate has moved westward over the hot spot.

Ocean acidification worsens overnight along California coast

Thu, 14 Jul 2016 13:39:01 -0400

A sampling pump and a sensor that measures temperature, salinity and depth sit in a tide pool at the University of California at Davis' Bodega Marine Reserve. Credit: Lester Kwiatkowski.

Carbon dioxide absorbed by the oceans causes seawater to become more acidic, which, as scientists have long been documenting, can negatively impact marine animals; for example, acidified waters damage the calcite skeletons and shells of organisms like coral, mussels and oysters by causing them to dissolve. In a new study, scientists have found that ocean seawater acidification may also be taking a toll on shelled organisms like coralline algae, bivalves and gastropods residing in tide pools along California’s coastlines.

Asian bats resist white nose fungus

Thu, 14 Jul 2016 10:36:04 -0400

White Nose Syndrome, seen here on a northern long-eared bat from Illinois, has killed millions of bats in North America since 2006. Credit: University of Illinois/Steve Taylor, CC BY 2.0.

White Nose Syndrome has devastated bats across North America in recent years, but possible genetic resistance to the fungus has now been identified in some species of Asian bats. Researchers comparing North American and Chinese bat populations in a new study have found lower levels of infection — and greater capacities for recovery — in bats from five cave sites in China.

Jawless fish more like jawed fish than thought

Thu, 14 Jul 2016 10:25:04 -0400

Lamprey eels do not have jaws; instead, they feed with a sucking mouth lined with teeth. Credit: Joanna Gilkeson, USFWS Midwest, CC BY 2.0.

Vertebrates come in all shapes and sizes, but the one thing almost all have in common are jaws, which developed early in vertebrate evolution. Jawless fish, which evolved about 530 million years ago and are thought to be more primitive than their jawed relatives, are an exception. According to a new study, however, the brains of jawless fish have more in common with the brains of jawed vertebrates than previously thought.

Denisovan DNA found in modern Pacific Islanders, ancient Spaniards

Thu, 14 Jul 2016 10:21:16 -0400

Denisovans were first identified from a 41,000-year-old finger bone found in a cave in Siberia. In two new studies, traces of Denisovan DNA have been found in modern Melanesians and in 430,000-year-old remains at the Sima de los Huesos site in Spain. Credit: K. Cantner, AGI.

In the time that Homo sapiens and Neanderthals were coexisting — and interbreeding — there was at least one more human species on the landscape, the Denisovans. First identified from a 41,000-year-old finger bone found in a cave in Siberia, the Denisovans are now thought to have been widespread around Eurasia. In two new studies, scientists have shed additional light on the relationship of Denisovans to other humans, finding new traces of Denisovan DNA in ancient and modern genomes.

Artists draw inspiration from fire and ash

Wed, 13 Jul 2016 10:13:28 -0400

In "Chichester Canal," British painter J.M.W. Turner's sunset glows with an ethereal quality that is attributed to volcanic aerosols in the skies across northern Europe during the "year without a summer" caused by the eruption of Mount Tambora in 1815. Credit: Tate Museum, London/Art Resource, NY.

I had a dream, which was not all a dream. The bright sun was extinguish’d, and the stars Did wander darkling in the eternal space, Rayless, and pathless, and the icy earth Swung blind and blackening in the moonless air; Morn came and went—and came, and brought no day.

Travels in Geology: Zermatt: Europe meets Africa in Switzerland's iconic Alps

Wed, 13 Jul 2016 09:53:22 -0400

Zermatt, Switzerland, is one of Europe’s premier tourist destinations, offering spectacular sightseeing, hiking and mountain climbing, as well as year-round skiing. The area’s popularity is rooted in its geology. Its high-grade metamorphic rocks and massive folds vividly narrate the story of the Alps’ formation, from the peregrinations of microcontinents during the breakup of Pangea to their assembly during the mighty Alpine Orogeny, the tectonic collision that raised the impressive mountain chain 40 million to 50 million years ago. More recently, massive glaciers sculpted this highland into today’s jagged peaks and deep valleys to create iconic glacial landscapes. Yet Zermatt’s scenic climax, one of the world’s most famous mountains — the Matterhorn — isn’t European at all; it was hewn from a slice of Africa.

Giant turbidite in Mediterranean Sea linked to ancient earthquake and tsunami

Tue, 12 Jul 2016 17:33:01 -0400

The Crete earthquake and tsunami in A.D. 365 devastated much of the Mediterranean. Credit: K. Cantner, AGI.

In A.D. 365, a giant earthquake with an estimated magnitude of 8 or higher struck the eastern Mediterranean, devastating Crete and causing widespread destruction throughout Greece, Egypt, Libya and Spain. The event was quickly followed by a tsunami that inundated the southern and eastern Mediterranean coasts, stranding ships as far as 3 kilometers inland. Now, scientists have uncovered evidence of a massive turbidity current triggered by these events in the Mediterranean.

Why is a gallon of gas cheaper than a gallon of milk?

Tue, 12 Jul 2016 17:16:53 -0400

For most of the last decade, the price of a gallon of milk has exceeded the price of a gallon of gasoline. Credit: data from U.S. Bureau of Labor Statistics Consumer Price Index; graph: Robert L. Fares.

I often tell people that one of the challenges associated with transitioning away from fossil fuels is that the amount of energy they contain is truly miraculous. A gallon of gasoline contains enough energy to push a modern sedan more than 30 miles down the road. Imagine throwing your car in neutral and pushing it for 30 miles — the energy required is roughly equivalent to the amount provided by that gallon of gasoline. Yet a gallon of gas weighs a mere six pounds and, on average in the U.S., costs just $2 to $3 — less than a gallon of milk. Truly miraculous.

Geoscience on Film: Innovation meets tradition for earthquake safety

Thu, 07 Jul 2016 14:17:51 -0400

Traditional Bhutanese rammed-earth houses sit amid rice terraces in Punakha Valley. Credit: Diane LaMacchia

Doug Prose, formerly a geologist with the U.S. Geological Survey, and his wife, Diane LaMacchia, have produced documentaries showcasing Earth and the geosciences through their nonprofit Earth Images Foundation since 1992. Recent films have included “Earth: The Inside Story” and “Italy’s Mystery Mountains,” both released in 2014 and aired on PBS. In spring 2015, Prose blogged for EARTH while filming on location in eastern and northern India for a documentary delving into the complex interplay of tectonics, natural hazards and humanity in the Himalayan region. Just weeks after departing, the massive Gorkha earthquake struck, severely damaging parts of Nepal, northern India and Tibet, and prompting LaMacchia and Prose to return to the region this June to investigate recovery efforts in the quake’s aftermath. Prose wrote about their recent experiences while there, and filed the following series of posts upon returning home. Read posts in this series, as well as from the 2015 trip, here.

On the trail of Hannibal's army - and elephants - in the Alps

Wed, 06 Jul 2016 17:18:33 -0400

In the third century B.C., during the Second Punic War between the Romans and Carthaginians, Carthaginian general Hannibal led a massive army over the Alps to invade Italy from the supposedly impenetrable north. It is one of the most famously brazen moves in military history, but the exact route that Hannibal’s army — which included tens of thousands of foot soldiers and cavalrymen, thousands of horses and nearly 40 elephants — took through the mountains has long been a mystery. Now, a team has found microbial evidence that a large number of horses crossed the Alps from France into Italy over the 3,000-meter Col de la Traversette pass around 218 B.C. But not everybody is convinced that the Traversette pass route matches detailed historical accounts of Hannibal’s journey.

Illustrating Geology: Great images that transformed the field

Wed, 06 Jul 2016 17:09:04 -0400

William Smith's famous geologic map of England, Wales and southern Scotland, published in 1815, featuring a labeled cross section of strata at middle right. The original map measured 2.6 meters by 1.8 meters and was assembled from 15 sections. Credit: courtesy of the Geological Society of London.

Last year marked the 200th anniversary of the publication of what many consider the greatest geologic image ever produced: William Smith’s epic map, entitled “A Delineation of the Strata of England and Wales with Part of Scotland.” In striking color, scale and detail, the 1815 map laid bare the region’s bedrock — from tilted layers of slate and fossil-rich marls and sandstones to Carboniferous coal seams and granite plugs — as none had before. The bicentennial of the map’s publication was commemorated in several sessions and displays at the annual meeting of the Geological Society of America (GSA) in Baltimore last October.

Benchmarks: March 1961: Project Mohole undertakes the first deep-ocean drilling

Wed, 06 Jul 2016 13:15:34 -0400

Early near-shore trials of the CUSS I drillship occurred off La Jolla, Calif., where the writer John Steinbeck noted that the barge, with its drilling derrick rising amidship, had the "sleek race lines of an outhouse standing on a garbage scow." Credit: Willard Bascom, National Academy of Sciences.

Since its inception in the 1960s, the ocean drilling program — an international research program that explores the world’s ocean basins — has logged hundreds of thousands of hours of ship time traveling the world’s oceans, drilling boreholes and retrieving cores of sediment and rock that have revealed Earth’s deep history and structure.

Geoscience on Film: Soaking in beautiful Bhutan

Wed, 06 Jul 2016 10:23:56 -0400

June 11, 2016

Mount Everest — seen here from the air on a flight from Kathmandu, Nepal, to Paro, Bhutan — towers above the clouds and other peaks in the high Himalayas. Credit: Doug Prose

The 50-minute Druk Air flight aboard a two-prop plane from Kathmandu to Paro, Bhutan, was one of the most incredible commercial flights I’ve ever experienced. The route parallels the great Himalayan peaks at a low altitude of 3,000 meters and about 25 kilometers to the south. Mount Everest (8,850 meters) on the border of Nepal and Tibet, Mount Kangchenjunga (8,590 meters) in India, and finally Bhutan’s second highest peak, Mount Jomolhari (7,325 meters), drifted by smoothly above the clouds. My clean, unscratched window afforded amazing shots that cannot be filmed any other way.

Benchmarks: October 1904: Mineralogy solves a murder

Wed, 06 Jul 2016 09:25:43 -0400

Credit: ©iStockphoto.com/mbbirdy.

Early forensic geology case makes headlines

In a bean field outside the city of Freiburg im Breisgau on the western edge of Germany’s Black Forest, Eva Disch lay dead, strangled. Her blue and red silk scarf may have kept the chill off her neck earlier on that October day in 1904, but now it was wound too tightly, a tourniquet around her neck. The only clue to the death of the local seamstress was a dirty handkerchief discarded near her body. With little evidence to go on, investigators turned to Georg Popp.

Benchmarks: August 1576: False gold found in Meta Incognita

Wed, 06 Jul 2016 09:10:08 -0400

This plate was published in 1595 in Mercator's Atlas. It records attempts by Frobisher, among others, to find a northwest passage, and shows the pole surrounded by islands between which rivers flow. Credit: ©National Maritime Museum, Greenwich, UK.

Three small boats set sail westward from London on June 7, 1576. Their goal: Find a northwest passage across the Arctic to Cathay, or China. A former pirate, Martin Frobisher, captained the 34 men. By July 11 they had reached Greenland. A storm overtook them, sinking one boat and forcing another to return home.

Late Antique Little Ice Age underpinned unrest and upheaval in Europe and Asia

Wed, 29 Jun 2016 10:45:15 -0400

Effects of climate change on society aren’t just a contemporary concern. A new study has found that a cold snap in the sixth and seventh centuries may have been the catalyst for a period of societal turmoil, marked by famine, plague and political tumult.

Getting there and getting around Michigan

Wed, 29 Jun 2016 10:27:29 -0400

The waterfalls at Pictured Rocks freeze in the wintertime, offering outdoor enthusiasts the chance to try their hands (and feet) at ice climbing during Michigan's annual Ice Fest. Credit: Lucas Joel.

The nearest city to Pictured Rocks National Lakeshore, the more remote of the two lakeshores, is Marquette, Mich., where travelers can fly into Sawyer International Airport, typically via connections through Chicago or Detroit. The closest town with lodging is Munising, right next to the lakeshore.

Legend of the Sleeping Bear

Wed, 29 Jun 2016 10:12:33 -0400

The dunes at Sleeping Bear Dunes are fantastic for hiking, snowshoeing, cross-country skiing, snowmobiling and sledding. Credit: left: ©iStockphoto.com/ RiverNorthPhotography; below: National Park Service

Sleeping Bear Dunes gets its name from a Chippewa legend that tells the story of a mother bear and her two cubs who, fleeing a fire in the woods of Wisconsin on the other side of Lake Michigan, plunged into the lake and began swimming to find safe haven. But the swim was tiring, and the cubs soon fell behind their mother. Upon reaching Michigan’s shores, the mother bear climbed out of the water, turned and watched, waiting for her cubs to join her. The cubs came into sight, but, too tired to finish the journey, they drowned just before reaching shore. The mother then lay down and fell into a slumber, forever awaiting her cubs. A spirit known as the Great Spirit Manitou created two islands — North and South Manitou islands — to commemorate the spot where the cubs’ journey ended, and then covered the mother with sand, forming the famous dune at the lakeshore.

Geoscience on Film: The view from outside Kathmandu

Tue, 28 Jun 2016 10:46:07 -0400

This school — seen here in June 2016 — was one of roughly 300 in Nepal that survived the intense shaking of the April 2015 Gorkha earthquake after it was retrofitted to withstand strong ground motion. Credit: Diane LaMacchia

Doug Prose, formerly a geologist with the U.S. Geological Survey, and his wife, Diane LaMacchia, have produced documentaries showcasing Earth and the geosciences through their nonprofit Earth Images Foundation since 1992. Recent films have included “Earth: The Inside Story” and “Italy’s Mystery Mountains," both released in 2014 and aired on PBS. In spring 2015, Prose blogged for EARTH while filming on location in eastern and northern India for a documentary delving into the complex interplay of tectonics, natural hazards and humanity in the Himalayan region. Just weeks after departing, the massive Gorkha earthquake struck, severely damaging parts of Nepal, northern India and Tibet, and prompting LaMacchia and Prose to return to the region this June to investigate recovery efforts in the quake’s aftermath. Prose wrote about their recent experiences while there, and filed the following series of posts upon returning home. Read posts in this series, as well as from the 2015 trip, here.

Geoscience on Film: Revisiting an earthquake-ravaged region, one year on

Fri, 24 Jun 2016 11:15:39 -0400

Damage overall in Kathmandu from the April 2015 Gorkha earthquake was lighter than anticipated, but it was different story in the city's historic Durbar Square, where the extensive damage is still obvious 14 months later. Credit: Doug Prose

Doug Prose, formerly a geologist with the U.S. Geological Survey, and his wife, Diane LaMacchia, have produced documentaries showcasing Earth and the geosciences through their nonprofit Earth Images Foundation since 1992. Recent films have included “Earth: The Inside Story” and “Italy’s Mystery Mountains," both released in 2014 and aired on PBS. In spring 2015, Prose blogged for EARTH while filming on location in eastern and northern India for a documentary delving into the complex interplay of tectonics, natural hazards and humanity in the Himalayan region. Just weeks after their departure, the massive Gorkha earthquake struck, severely damaging parts of Nepal, northern India and Tibet, and prompting LaMacchia and Prose to return to the region this June to investigate recovery efforts in the quake’s aftermath. Prose wrote about their recent experiences while there, and filed the following series of posts upon returning home. Read posts in this series, as well as from the 2015 trip, here.

Benchmarks: January 23, 1960: Humans reach the deepest point on Earth

Mon, 20 Jun 2016 14:40:15 -0400

Jacques Piccard and Don Walsh in the crew cabin as the Trieste descends to Challenger Deep. Credit: NOAA.

More than 9,000 meters underwater, a window buckles, sending a spider web of cracks across the glass. The entire submersible shakes, but no water rushes into the Trieste. Out of vocal contact with the main ship on the surface above them, Swiss oceanographer and engineer Jacques Piccard and U.S. Navy Lt. Don Walsh decide to continue their descent despite the new danger. After all, at more than nine kilometers below the sea surface, the explorers were too close to their goal to turn around. They were only 2,000 meters away from the deepest spot on Earth: Challenger Deep. On Jan. 23, 1960, they reached that fabled point 10,916 meters below the surface of the Pacific Ocean.

The first dinner in a beast

Mon, 20 Jun 2016 14:06:10 -0400

Hawkins with his statue of the Irish elk, Megaloceros, circa 1853. Credit: Academy of Natural Sciences, Ewell Sale Stewart Library and the Albert M. Greenfi eld Digital Imaging Center for Collections.

Surprisingly, there is precedence for eating dinner in the body of a massive beast. In February 1802, Rembrandt Peale, an early American painter best known for his portraits of George Washington and Thomas Jefferson, invited 12 friends and family to dine under the rib cage of a mammoth, which had recently been erected in his father’s museum in Philadelphia.

Benchmarks: December 31, 1853: Dinner in a dinosaur

Mon, 20 Jun 2016 13:27:44 -0400

On New Year's Eve, 1853, Benjamin Waterhouse Hawkins hosted a formal dinner in the mold of an Iguanodon. Credit: Academy of Natural Sciences, Ewell Sale Stewart Library and the Albert M. Greenfield Digital Imaging Center for Collections.

The weather in London on Saturday, Dec. 31, 1853, could not have pleased Benjamin Waterhouse Hawkins. After a relatively warm Friday, the temperature had plummeted, snow had begun to fall, and for the first time in more than a decade, masses of ice floated down the Thames River. The snow made the streets so slippery that injured pedestrians filled the hospitals.

Benchmarks: November 27, 1873: Red River logjam removed for good

Mon, 20 Jun 2016 10:29:43 -0400

Throughout the 1800s, America’s eastern and southeastern coastal rivers acted as highways for shipping. Generally winding with shallow slopes, the rivers could be plied easily by barges and steamboats, but one particular water body — the main channel of the Red River that runs from Arkansas through Louisiana — thwarted the plans of shippers for much of the 19th century. A massive entanglement of logs, stumps and branches, known as the Great Raft, blocked the Red from Fulton, Ark, to about Shreveport, La. But on Nov. 27, 1873, after more than 40 years of trying, the raft was destroyed and boats could travel unimpeded down the main channel of the Red River.

From science to science fiction

Mon, 20 Jun 2016 09:58:15 -0400

Project Cirrus may have flopped in the meteorology world, but its research left an indelible impression on the literary world.

Legend has it that Irving Langmuir, future head of Project Cirrus, was showing author H.G. Wells around the General Electric labs sometime around 1930. During the tour, Langmuir allegedly began talking about water that was solid at room temperature, an idea that he thought Wells could use for a story. When Kurt Vonnegut began working at GE’s press office in 1947, he discovered the story about Wells and Langmuir. And thus, the seed of the fabled ice-nine — the chemical catalyst behind the global catastrophe that is the centerpiece of Vonnegut’s “Cat’s Cradle” — was planted in the author’s mind.

Benchmarks: October 13, 1947: A disaster with Project Cirrus

Mon, 20 Jun 2016 09:44:35 -0400

Bernard Vonnegut and Vincent Schaefer examine preserved snowflakes on a sheet of glass in 1951. Credit: Schenectady Museum & Suits-Bueche Planetarium.

Two days after clipping Cuba and Florida, a hurricane was drifting out into the Atlantic. All predictions had it remaining at sea without further landfall, making it the perfect test subject for the newly minted Project Cirrus, a U.S. government- backed project bent on discovering a way to disable deadly hurricanes. The researchers planned to seed the hurricane’s clouds with dry ice, hoping that the ice would interact with the clouds and disrupt the cyclone’s internal structure, thus weakening it. So on Oct. 13, 1947, a plane flew over the storm and dumped 80 kilograms of dry ice into the storm’s swirling clouds.

Travels in Geology: Sculptures of wind and ice: Sleeping Bear Dunes and Pictured Rocks National Lakeshores

Fri, 17 Jun 2016 16:35:06 -0400

View of Sleeping Bear Dunes National Lakeshore along Lake Michigan, as seen from the end of the Empire Bluff Trail. South Manitou Island can be seen in the distance. Credit: National Park Service.

Two of the U.S.'s four national lakeshores are in Michigan: Sleeping Bear Dunes and Pictured Rocks. Credit: all: K. Cantner, AGI.

Empire Bluff trailhead at Sleeping Bear Dunes. Credit: National Park Service.

During the Pleistocene, the Laurentide Ice Sheet, which covered much of North America, gouged large valleys that would one day become the Great Lakes. Today, four of these lakes border Michigan, giving the state’s Lower Peninsula its famed mitten shape and setting much of the Upper Peninsula off on its own. The ice sheet no longer exists, but travelers can visit scenic spots in Michigan — along the mitten’s edges and in its distant provinces — that only came to be because of the ice sheet’s erosive work. Among them are two of the country’s four U.S. national lakeshores, which are managed by the National Park Service: Sleeping Bear Dunes and Pictured Rocks.

Geology shaped outcomes of Civil War battles

Fri, 17 Jun 2016 16:26:04 -0400

As demonstrated here by Civil War reenactors in 2014, gaps naturally carved into limestone outcrops, called karrens or cutters, provided opportune defensive positions from which retreating Union forces staved off advancing Confederate soldiers while awaiting reinforcements during the Battle of Stones River (Tennessee) in December 1862. Credit: Scott P. Hippensteel and Geosphere.

About 10 years ago, Scott Hippensteel decided to trace the footsteps of an ancestor who fought in the Civil War at the Battle of Antietam near Sharpsburg, Md. His relative, William H. Tritt, fought with the Union in the 130th Pennsylvania Volunteer Infantry, which, on Sept. 17, 1862, attacked Confederate soldiers entrenched in the infamous Sunken Road, a wagon-worn dirt road atop an embankment that farmers used to bypass the town. As Hippensteel walked the rolling topography himself, he quickly realized the tactical advantage the landscape afforded: The Union men became visible to their enemies only in the last 150 meters or so of their approach. Because of the single-shot rifle technology of the time, each Confederate soldier would have only had time to fire a few shots at their attackers, facilitating a more vigorous assault by the Union. The Union forces suffered heavy losses in driving the Confederates from the Sunken Road, but their ultimate success pierced the middle of the Confederate line at Antietam and led to the roadway being renamed “Bloody Lane."

Geologic Column: The dog days of July

Fri, 17 Jun 2016 16:10:35 -0400

Julius Ceasar, for whom two months in the Gregorian Calendar of the year are named. Credit: ©Traumrune / Wikimedia Commons / CC-BY-SA-3.0.

As months go, July has some distinctive qualities. For one thing, it is one of only two months in the Gregorian calendar named for a person; in this case, Julius Caesar. (The other is August, which honors Julius Caesar’s great nephew and the first Roman emperor, Gaius Octavius, better known as Augustus.) The remaining months of the year are named for gods, goddesses, festivals or numbers.

Comment: What's a map worth? The big cost and bigger benefit of three-dimensional elevation data

Fri, 17 Jun 2016 13:05:31 -0400

Map of the areal extent and quality of planned, in progress and existing publicly available lidar and InSAR/IfSAR data that meet the specifications of the 3DEP program. Credit: 3DEP.

High-resolution topographic data are critical for a number of tasks — from managing flood risks to ensuring aviation safety to mapping hiking trails. In the past, such data came from careful analysis of aerial photos, but today, researchers have at their fingertips a suite of remote sensing technologies that can record ground-surface elevation — even when the ground is obscured by thick summer foliage, winter snow and ice, or dense cloud cover.

Iron meteorites likely hidden below Antarctic ice

Thu, 16 Jun 2016 13:33:04 -0400

Antarctica has yielded two-thirds (about 35,000) of all the meteorites that have ever been discovered on Earth. Credit: NASA.

Despite the fact that meteorites fall relatively evenly across the surface of the planet, most meteorites retrieved by humans have come from Antarctica. This is because meteorites are easily buried and preserved in Antarctic ice; over time, the ice melts and exposes the dark-colored fallen rocks for relatively easy recovery on the continent’s white surface. But iron-rich meteorites, common among specimens found in other parts of the planet, are unusually rare in Antarctica. Researchers may now have figured out why.

Slow-moving super-eruptions still travel great distances

Thu, 16 Jun 2016 10:06:26 -0400

Deposits of Peach Spring Tuff from a super-eruption 18.8 million years ago can be seen throughout Arizona, Nevada and Southern California. Credit: David Buesch.

When Hollywood movies depict the destruction unleashed by volcanic eruptions, they usually focus on red-hot lava, but even more dangerous are pyroclastic flows: mixtures of rocky debris and searing hot ash and gas that move as fast as 700 kilometers per hour and can bulldoze, incinerate and suffocate anything in their paths. In a new study looking at pyroclastic flow deposits associated with the Silver Creek Caldera in the southwestern U.S., researchers have found that not all pyroclastic flows are so swift. Dense, slow-moving flows can still wreak havoc over vast distances.

Weak magnetic field may have triggered Earth's first mass extinction

Thu, 16 Jun 2016 10:00:57 -0400

A section of the Ediacaran-aged Zigan Formation in the Ural Mountains of Russia. The Zigan was sampled by Joseph Meert and his team for paleomagnetic signatures. Credit: Mikhail Bazhenov.

For about the first 3 billion years of life, the only living organisms on Earth were microscopic. The Ediacaran Period, between 635 million and 541 million years ago, saw the rise of the first large-scale life, most of which then went extinct at the period’s close — a collapse that scientists have yet to explain. Now, researchers may have found one of the extinction’s drivers: rapid flip-flopping of Earth’s magnetic field — wherein the field’s north and south poles reverse — that could have left the planet and Ediacaran organisms vulnerable to bombardment by harmful cosmic radiation.

Take a stand (or sit) for better water quality management

Thu, 16 Jun 2016 09:42:20 -0400

Referred to as "separation," "urine diversion" or "no-mix" toilets, the toilets of the future look, on the outside, like typical toilets today. The insides of the bowls are divided into two collection areas — one at the front for urine and another at the back for feces. Credit: Eawag, Ruedi Keller

The average person urinates four to seven times over a 24-hour period, producing about 1.5 liters of urine per day. Here are some things you can do today to help conserve water, improve water quality, and keep all that waste from going to waste.

'P' is for phosphate: Could urine solve a fertilizer shortage?

Thu, 16 Jun 2016 09:26:37 -0400

Researchers at the Rich Earth Institute are experimenting with using urine-derived fertilizer to grow crops. Here, institute researcher Abe Noe-Hays adds sanitized urine fertilizer to lettuce. Credit: Marcin Szczepanski.

Whether you’re enjoying a juicy burger from a fast-food drive-thru or digging into a brightly colored salad at a backyard barbecue, your meal likely started life on a farm. Each day, agriculture around the world produces an average of 27.3 million tons of food, enough to feed Earth’s current population of about 7.3 billion — although not all of that food reaches people.

Searching for the ancestors of meandering rivers

Wed, 15 Jun 2016 12:16:31 -0400

In outcrops of the Tombador Formation in the Bahia state of Brazil, researchers found evidence of ancient channel-braided rivers — which combined traits of modern sheet-braided and meandering rivers — that existed before plants colonized land. Credit: Bruno Boito Turra.

It might be difficult to imagine Earth devoid of vegetation, but for billions of years the sun shone, winds blew and rivers flowed on a planet without any plants.

A new gravity map of Earth

Wed, 15 Jun 2016 12:08:01 -0400

This portion of the new whole-Earth gravity map shows gravity gradients in the North Atlantic. Credit: Johannes Bouman/TUM.

Gravity differs from place to place around Earth because of the uneven distribution of mass across and within the planet. Scientists can study the variation in gravitational pull by measuring the gravity field at different places on the surface of the planet. In a new study published in Scientific Reports, gravity field data collected over the entire planet between 2009 and 2013 by the European Space Agency’s Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) satellite has been mapped, revealing many of Earth’s internal features, such as magmatic plumes welling up toward the surface.

A labyrinth of silver mines uncovered on the shores of the Aegean Sea

Wed, 15 Jun 2016 11:29:05 -0400

A mining archaeologist at work in a 5,000-year-old silver mine in Thorikos, Greece. Credit: Ghent University.

By the fifth and fourth centuries B.C., silver mines under the ancient Greek city of Thorikos, now known as Lavrio, were the most important mines in Greece. Recent underground exploration of the network of tunnels found at the foot of the city’s Mycenaean-aged Acropolis is shedding new light on the scale — and miserable conditions — of the mines.

Geomedia: Television: 'NOVA' for the earth science enthusiast

Tue, 14 Jun 2016 18:11:30 -0400

Three recent earth science-themed NOVA episodes have examined the possible roles of rocks and minerals in the emergence of life on early Earth, the April 2015 earthquake that struck Nepal, and the persistent hazard of sinkholes in some parts of the world. Credit: left: CC0 public domain; middle: Jessica Lea/UK Department for International Development, CC BY 2.0; right: Ann Tihansky/U.S. Geological Survey

“NOVA,” the weekly prime-time science series that airs on PBS, is known for producing high-quality TV documentaries on subjects ranging from espionage and the military to ancient civilizations and nature. Naturally, much “NOVA” programming touches on topics in geoscience, so we decided to review several recent hour-long episodes that might be of particular interest to our readers. To find out about upcoming broadcasts or watch episodes online, visit http://www.pbs.org/wgbh/nova/.

Benchmarks: September 21, 1930: Alfred Wegener begins a fateful polar expedition

Tue, 14 Jun 2016 09:53:23 -0400

Members of the 1930 expedition, left to right: Johannes Georgi, Alfred Wegener, Fritz Loewe, Ernst Sorge. Credit: Archive of Alfred Wegener Institute.

Alfred Wegener (right) during the 1930 expedition and overwintering in Greenland. Credit: Archive of Alfred Wegener Institute.

In September 1930, 15 polar explorers set out from their base camp at Kamarujuk on the west coast of Greenland. The team was carrying much-needed supplies 400 kilometers inland to two meteorologists waiting at a satellite camp at Eismitte at the center of the Greenland icecap. The team, consisting of German meteorologists Alfred Wegener and Fritz Loewe as well as 13 Greenlanders, traveled slowly, their dogsleds hindered by storms and frigid temperatures. All but Wegener, Loewe and one Greenlander, Rasmus Villumsen, were forced to turn back by the blizzards. At last, the three explorers managed to reach the icecap camp at the end of October.

Getting there and getting around Turkey

Wed, 01 Jun 2016 10:06:12 -0400

Private boats to visit the Sunken City are surprisingly affordable along the Turquoise Coast. Credit: Terri Cook and Lon Abbott.

Turkey has two major airports — Istanbul and Ankara — and many smaller regional ones. Istanbul Ataturk Airport offers nonstop flights on Turkish Airlines from several U.S. cities, including New York, Chicago, Atlanta, Los Angeles and San Francisco. To enter the country, Americans need a visa; these can be quickly obtained online.

Benchmarks: June 4, 1783: The era of aviation launches with the first balloon flight

Thu, 26 May 2016 15:55:41 -0400

A crowd of peasants attacked the first hydrogen balloon in Gonesse, France, in August 1783. Credit: public domain.

In the small French town of Gonesse in August 1783, a large, spherical and nebulous object painted with red and yellow stripes fell from the sky and began fluttering about on the ground. The town’s peasants, fearful, attacked the object with pitchforks, and then tied it to a horse’s tail to be dragged through the streets.

Seeing the seafloor in high definition: Modern mapping offers increasing clarity on Earth's vast underwater landscape

Fri, 20 May 2016 16:03:01 -0400

In the 1950s, Marie Tharp and Bruce Heezen, of what was then called the Lamont Geological Observatory, began creating seafloor maps based on single-beam sounding data from the U.S. Navy and other sources. Their compilation map of the global seafloor was published in 1977. Credit: Library of Congress, Geography and Map Division.

Gliding through pitch-black waters 50 meters off the ocean bottom, the “D. Allan B” can sense the seafloor below in striking clarity, despite the darkness. In its backyard off the California coast, the 5-meter-long, torpedo-shaped autonomous underwater vehicle (AUV) operated by the Monterey Bay Aquarium Research Institute (MBARI) has surveyed submarine topography ranging from deep canyons incising the continental shelf to subtle scarps weaving through blankets of ocean-bottom sediments. Since entering operation about a decade ago, the AUV’s mapping prowess — it can distinguish features less than a meter wide and just 10 centimeters tall, a level of precision that rivals NASA’s Mars-mapping HiRISE camera — has become an integral tool in MBARI’s efforts to study Earth’s surface beneath the waves.

Ice (Re)Cap: June 2016

Fri, 20 May 2016 13:05:31 -0400

Phosphorus-rich meltwater flows from the Leverett Glacier in southwest Greenland. Credit: Jon Hawkings.

Underwater Roman marble traced to Greece, Italy and Turkey

Fri, 20 May 2016 12:56:15 -0400

Scientists take the plunge underwater to analyze one of the most valuable materials used to construct affluent Roman villas: white marble. Credit: courtesy of Michela Ricca et al..

From the first century B.C. to the third century A.D., the city of Baiae, located on the west coast of Italy, near Naples, was the preferred summer home of Roman emperors, including Augustus and Nero. The once-grand city now lies under more than 5 meters of water due to coastal subsidence, and is preserved as the Underwater Archaeological Park of Baiae. Researchers have now traced the opulent city’s white marble floors to some of the most famous quarries in Italy, Greece and Turkey.

Social trends and shifting climates had complex effects in medieval Italy

Fri, 20 May 2016 12:50:33 -0400

Researchers combined written historical records housed in the Abbey of Farfa and Rieti Cathedral, seen here, with environmental records from sediment and pollen to see how the landscape of Italy's Rieti Valley changed through medieval times. Credit: Alessandro Antonelli, CC BY 3.0.

It’s easy to anecdotally pin environmental changes and their societal impacts on shifting climates. But when scientists and historians came together to look at environmental changes through the warm Medieval Climate Anomaly and cold Little Ice Age in Rieti, Italy, they found that the real story of climate and social change is much more complex — and interesting.

Above oil seeps, photosynthetic life flourishes

Thu, 19 May 2016 22:04:40 -0400

Researchers found that phytoplankton abundances in the Gulf of Mexico were higher in the water column above naturally occurring oil and gas seeps than in nearby areas not above seeps. Credit: NASA.

The direct effects of oil and gas releases in the ocean are typically negative — as in the case of 2010’s Deepwater Horizon oil well disaster, which devastated marine ecosystems in the Gulf of Mexico. But scientists have now found that when natural oil and gas seeps upwell toward the ocean’s surface, they can also carry nutrients such as nitrates and nitrites from the seafloor that feed communities of phytoplankton, which flourish as a result.

Measuring rising seas is tricky in deltas

Thu, 19 May 2016 16:38:36 -0400

Researchers used an experimental basin filled with water and sand-, silt- and clay-sized sediments to mimic natural deltas and study the formation and preservation of stratigraphic records. Credit: Kyle Straub.

Earth’s stratigraphic record offers a patchwork diary of how different parts of the planet have formed and changed over time. Some of the most extensive pieces of the stratigraphic record are found in deltas, making them ideal places to look for long-term chronicles of Earth’s history, as well as clues to future changes to our coastal landscapes.

Lack of fungi did not lead to copious Carboniferous coal

Thu, 19 May 2016 16:27:03 -0400

The majority of the world's coal dates to the Carboniferous Period. Credit: Mary Caperton Morton.

The Carboniferous Period is famous for supplying Earth with an abundance of coal deposits. According to one hypothesis, the formation of all this coal is explained by a proposed 60-million-year gap, or lag, between the spread of the forests globally about 360 million years ago and the rise of wood-eating microbes and fungi that could break down tough plant matter. But a new study refutes this idea, instead attributing the Carboniferous’ copious coal to the consolidation of the supercontinent Pangea.

Radar reveals unmarked graves

Mon, 16 May 2016 11:30:53 -0400

Kevin Williams (left) and Trevor Jennings conduct a ground-penetrating radar survey at a cemetery in western New York. Credit: courtesy of Kevin Williams.

The occasional excursion to Death Valley or mineralogical study of bloodstone notwithstanding, geoscientists don’t often delve into the macabre in the course of their work. But when the administrators of two cemeteries in western New York came calling in 2014, researchers from Buffalo State College ended up using their geophysical field skills to hunt for centuries-old graves.

Mesa Arch's 'hum' measured to track health of rock structure

Wed, 11 May 2016 10:46:55 -0400

Researchers applied structural health monitoring to study the stability of a natural arch — Mesa Arch in Utah's Canyonlands National Park — for the first time in a recent study. Credit: Jeffrey Moore

For decades, structural engineers have listened to the tiny vibrations of buildings and bridges to detect internal damage or weakness. In recent years, geoscientists have begun employing this technique, called “structural health monitoring,” to discover the hidden inner workings of natural rock features. In a recent study, researchers have applied this method for the first time to examine a rock arch — Utah’s famous Mesa Arch — to determine whether this delicate structure is stable or soon to collapse.

Giant icebergs spur carbon storage in Southern Ocean

Mon, 09 May 2016 15:38:41 -0400

Dozens of giant icebergs are currently floating in the Southern Ocean, with more projected to calve in the coming years. Credit: Patrick Rowe, National Science Foundation.

A new study shows that giant icebergs floating in the Southern Ocean around Antarctica may be playing a larger role in carbon sequestration and Earth’s global carbon cycle than previously thought.

Down to Earth With: Ethnogeologist Steven Semken

Fri, 22 Apr 2016 11:26:48 -0400

Steven Semken, an associate professor of geology and education and associate director for community outreach in the School of Earth and Space Exploration at Arizona State University, discussing the geology of the Colorado Plateau above the San Juan River goosenecks in Utah. Credit: Alissa Schlecht, University of Utah.

Semken was fascinated by rocks and minerals. His father, a banker, and his mother, a municipal tax collector, loved to travel and frequently indulged their son’s yen for sparkling specimens. They also bought Semken numerous books about geography and geology, including “The Big Golden Book of Geology,” which made such an impression that his childhood copy still sits on his office shelf. Semken vividly remembers staring at the book’s picture of Ship Rock, a towering volcanic neck on the Navajo Nation in northwestern New Mexico. Little did he know that he would later spend 15 years living and teaching geology with that Ship Rock as a backdrop.

Did the Medieval Warm Period welcome Vikings to Greenland?

Thu, 21 Apr 2016 16:59:40 -0400

The Vikings first colonized Greenland in A.D. 985 and made a living primarily as dairy farmers for more than 400 years before abandoning the settlements. Credit: Nicolás Young.

Vikings are often depicted as hardy folk and fearsome warriors, but they were not immune to the harsh realities of the northern latitudes. Archaeological evidence suggests that Viking migrations around the North Atlantic were highly influenced by climate, with new settlements being colonized during warm periods and abruptly abandoned during colder times. However, according to a new study of glacial movements in Greenland during the time of Viking occupation, the local climate may have been just as cold when the Vikings arrived as when they left 400 years later. The finding may further shrink the area thought to have been affected by the Medieval Warm Period.

Growth rings in rocks reveal past climate

Thu, 21 Apr 2016 16:54:22 -0400

This cobble is coated with calcite layers that record 150,000 years of climate data. Credit: Warren Sharp and Erik Oerter.

Paleoclimate studies often depend on mineral or sediment layers deposited seasonally or annually in caves, lakes and ice, but such records leave gaps where caves, lakes or ice sheets aren’t found. Now, scientists using a new technique that analyzes calcite layers ringing pebbles and rocks in arid landscapes are opening a new window onto the climate history of western North America. And because such deposits are found all over the world, the technique might prove to be a useful new tool for studying paleoclimate globally.

Looking for life in coldest, driest Antarctica

Thu, 21 Apr 2016 16:17:08 -0400

Researchers studying permafrost samples from University Valley in Antarctica's McMurdo Dry Valleys region found no signs of active microbial life. Credit: Jacqueline Goordial.

Antarctica is nicknamed the “White Continent,” but one site — University Valley in the continent’s McMurdo Dry Valleys region — has remained virtually snow-free for more than 150,000 years, making it the coldest, driest desert on Earth. For the past four years, researchers involved in NASA’s ASTEP (Astrobiology Science and Technology for Exploring Planets) program searched for signs of life in the valley because it is thought to closely resemble the northern polar regions of Mars where the Phoenix spacecraft landed in 2008. In a new study, though, the team reports that it came up empty-handed, confirming that University Valley is indeed one of the least-habitable places on Earth.

Fish evolved quickly after earthquake

Thu, 21 Apr 2016 16:10:05 -0400

A male three-spined stickleback. Credit: Mark Currey.

Evolution is often thought of as occurring over very long timescales, but as a tiny Alaskan fish demonstrates, significant changes can take place in just a few generations.

Geologic Column: May: Nature's forces in collision

Thu, 21 Apr 2016 16:01:19 -0400

As a day, May 1 has probably had more festivals and events associated with it than any other day of the year. Credit: Copyright Corbis Images.

May is named for Maia, the Greek goddess of fertility, and eldest of the seven Pleiades sisters. Orion, the hunter, after meeting the sisters, was so enamored of the young women that he pursued them relentlessly. Taking pity on their plight, Zeus changed the sisters into a flock of doves and set them in the heavens as a striking constellation of stars in the northeast quadrant of the sky. Maia’s festival was held at the beginning of May and celebrated with spring flowers and blooms.

Mercury levels support volcanic role in end-Cretaceous extinction

Thu, 21 Apr 2016 15:32:54 -0400

In sedimentary rock near Bidart, France, scientists found high levels of mercury associated with the eruption of the massive Deccan Traps flood basalts about 66 million years ago. Credit: Eric Font.

The end-Cretaceous extinction, known for finishing off the last dinosaurs about 66 million years ago, often evokes scenes of a large asteroid hurtling toward Earth. However, new evidence supports a growing consensus that the massive bolide wasn’t the only hazard that life on Earth had to contend with: A prolonged bout of major volcanic eruptions was also spewing climate-altering gases and other emissions such as mercury into the atmosphere.

First all-digital geologic map of Alaska released

Thu, 21 Apr 2016 14:36:16 -0400

The Anchorage area is shown in this portion of the new digital geologic map of Alaska. The full map is available at https://pubs.er.usgs.gov/. Credit: U.S. Geological Survey.

When it comes to natural beauty, Alaska’s rugged, massive landscape is an embarrassment of riches, with towering mountains and lush forests, countless islands and a seemingly endless coastline. Below the surface, it features a wealth of interesting geology and abundant resources. Now, policymakers, land managers, scientists and the public can all explore Alaska a little more deeply with the recent release of the first-ever fully digital geologic map of the entire state.

Reading the ridges: Are climate and the seafloor connected?

Tue, 19 Apr 2016 17:38:41 -0400

New research suggests that the spacing and elevation of abyssal hills at mid-ocean ridges — traditionally thought to form by faulting — could be correlated with past changes in global sea levels. Credit: K. Cantner, AGI.

At the bottom of every ocean basin lies a chain of submarine mountains. Blanketed in black, pillowy basalt, they tower more than a thousand meters above the seafloor and snake for thousands of kilometers. But instead of having a central spine, like a terrestrial mountain range, these mid-ocean ridges have a central trough from hundreds to thousands of meters wide. This is where — in fiery bursts — new oceanic crust is born.

Magnesium part of Earth's magnetic field engine

Tue, 19 Apr 2016 15:47:36 -0400

An artist's interpretation of how the precipitation of buoyant magnesium-bearing minerals, which rise toward the core-mantle boundary, from the otherwise iron-rich core could drive compositional convection and help drive Earth's geodynamo. Credit: reprinted from Nature with permission.

Earth’s magnetic field, which arises from convective flows in the planet’s core, known as the geodynamo, has existed for at least 3.4 billion years, meaning that the field-generating processes must have existed for that long as well. But what exactly those processes have looked like throughout Earth’s history, particularly early on, has been poorly understood. In a new study, researchers suggest that magnesium mineral formation in the core is a previously unrecognized but important piece of the puzzle.

Model targets better understanding of recurring Indian-Pacific storm systems

Tue, 19 Apr 2016 15:45:24 -0400

Scientists have known for decades that the Madden-Julian Oscillation (MJO) — a massive gathering of thunderstorms that forms intermittently over the Indian and western Pacific oceans — impacts regional and global weather. Predicting the impacts, however, has been more difficult because relatively little is known about the phenomenon, at least compared to El Niño and some other weather patterns. But in a new study, scientists have devised a mathematical model that clarifies how the MJO develops and progresses, which may pave the way for more accurate predictions of its effects.

Humans evolved early to be more efficient sleepers

Tue, 19 Apr 2016 15:41:39 -0400

Chimpanzees sleep an average of 11.5 hours per day, usually in a tree nest, whereas humans snooze for just seven hours. Credit: Kathelijne Koops, University of Zurich, Switzerland.

We humans spend about a third of our lives asleep. While that might sound like a lot, we require less sleep than most mammals. In a new study, researchers have quantified how much less sleep we need than other primates, and the findings may offer clues to how and when human sleep patterns evolved.

The softer side of hydrothermal vents

Tue, 19 Apr 2016 15:34:36 -0400

A 3-meter-tall talc spire tops the main hydrothermal vent in the Von Damm Vent Field. Credit: National Oceanography Center Southampton.

Seafloor chimneys belching dark plumes of superheated, acidic fluids into the ocean, called “black smokers,” are the most common kind of submarine hydrothermal vent known. But recently scientists discovered a vent system, of a seemingly gentler nature, unlike any observed before.

Benchmarks: April 22, 1995: GLOBE is launched

Wed, 13 Apr 2016 18:16:03 -0400

Over the last 20 years, GLOBE students have collected 130 million environmental observations, often without the use of sophisticated instruments. To calculate tree heights (left), students make and use a simple clinometer to measure the angle between the ground and the treetops. To measure clouds (right), students divide the sky into quadrants using their raised arms, then identify cloud types and estimate coverage in each quadrant. Credit: both: courtesy of The Globe Program/All Rights Reserved.

Studying the global environment requires collecting numerous detailed observations. And although it may seem today like we’re awash in such data, relevant observations — collected at the right time and place — are often unavailable. For example, scientists studying precipitation must rely on just a handful of sampling stations: All of the world’s raingages gathered together would only cover an area the size of two basketball courts.

Down to Earth With: Tectonicist Eldridge Moores

Wed, 13 Apr 2016 18:00:05 -0400

Eldridge Moores at the Cordelia Fault, a branch of the San Andreas Fault in the northern Coast Ranges, on a field trip for the general public in March 2010. Credit: Judy Moores.

“When Eldridge Moores was 10 years old, his family lived in Crown King, Ariz., a tiny, remote mining settlement high in the rugged Yavapai Mountains northwest of Phoenix. Money was tight and his family rarely traveled, so Moores vividly remembers a holiday road trip to visit his father’s relatives near San Francisco. The Bay Area left a deep impression on Moores, and, at the end of the journey, upon reaching the first of four switchbacks on the narrow dirt track that led up to Crown King, Moores vehemently pronounced that he would do everything he could to get out of there.

Geologic Column: At the end of the Earth

Wed, 13 Apr 2016 17:25:17 -0400

When you think of Spain, what images come to mind? The impoverished sailor from Genoa who was bankrolled by Queen Isabella to sail westward looking for China, but found a New World instead? The conquistadors who used guns, germs, steel and horses to topple two great civilizations? Or (my favorite) a fictional madman called Quixote who tilted at windmills?

Ice (Re)Cap: April 2016

Wed, 13 Apr 2016 17:09:04 -0400

Thawing permafrost in Alaska, which can lead to slope failures like this one along the Noatak River, may increase dramatically this century as air and ground temperatures rise. Credit: Rory Nichols.

Comment: How long have humans been altering Earth's climate?

Thu, 07 Apr 2016 18:48:29 -0400

The early anthropogenic hypothesis holds that prolonged warmth in the Holocene was caused by early agriculture. Paleoclimatologists have long sought an analog of the current Holocene interglaciation. Here, precession (A) and obliquity (B), which impact solar insolation, and atmospheric carbon dioxide concentrations (C) of previous interglaciations are compared with the Holocene (stage 1). The closest analog to the Holocene is stage 19, which began about 787,000 years ago. Credit: Ruddiman et al., Review of Geophysics, 2016.

Throughout the 20th century the paleoclimate science community regarded the warmth of the current (Holocene) interglaciation — prior to the major anthropogenic intervention of the last 150 years — as overwhelmingly natural in origin. In this view, changes in Earth’s orbit had resulted in increased summer insolation at high latitudes of the Northern Hemisphere, which began melting the North American and Scandinavian ice sheets 17,000 years ago and eventually ushered in interglacial warmth. Although further orbital shifts then led summer insolation to begin decreasing 10,000 years ago, the drop was thought not to have been substantial enough to cause renewed glaciation.

An absentee note for ancient blueschist: Lack of metamorphic rock does not date onset of plate tectonics

Fri, 01 Apr 2016 12:19:51 -0400

Blueschist (left) and greenschist (right) are both metamorphic rocks that form in subduction zones, but under different thermodynamic conditions. Credit: both: Callan Bentley.

Plate tectonics is a defining characteristic of our 4.5-billion-year-old home planet, responsible for earthquakes, mountain building, and much of the evolution of the planet’s oceans and atmosphere. But when this formative process began is a mystery. Some researchers have pointed to the lack of blueschist — a type of metamorphic rock that only forms in tectonically driven subduction zones — in rocks older than 800 million years as a clue to when subduction began. But a new study rules this option out, offering a novel explanation for the rock’s absence in ancient rocks.

North Sea uplift caused Jurassic cooling event

Wed, 30 Mar 2016 19:02:35 -0400

The Laurasian Seaway (a) connected the Boreal Sea to the Tethys Ocean to the south during the Jurassic. Uplift of the North Sea Dome (b) beginning in the Early Jurassic might have blocked the northward flow of warm Tethyan waters through the seaway, causing an abrupt cooling event about 174 million years ago. Credit: Korte et al., Nature Communications, December 2015, CC BY 4.0.

The climate of the Jurassic, long envisioned as ubiquitously warm from the equator to the poles, was actually more dynamic, sometimes cooling dramatically, according to a new study. The research joined isotopic and sedimentological data to suggest that an abrupt cooling event occurred in the midlatitudes early in the Middle Jurassic as a result of changing ocean currents associated with a feature known as the North Sea Dome.

Going with the flow: Mapping the mantle under the Cascadia Subduction Zone

Tue, 22 Mar 2016 19:44:36 -0400

A new study using seafloor seismic instruments has revealed more information about the complex and dangerous Cascadia Subduction Zone. Credit: K. Cantner, AGI.

The Cascadia Subduction Zone (CSZ), off the Pacific Northwest coast of the United States and Canada, is one of the world’s most mysterious — and potentially dangerous — earthquake zones. Eerily quiet since a massive magnitude-9 event in 1700, scientists have long warned that the 1,000-kilometer-long fault zone could produce another devastating earthquake and tsunami. Now, a new effort to map the fault zone’s tectonic environment, including the underlying mantle, is shedding light on some of the dynamic forces that may influence earthquakes in the region.

Underground ants can't take the heat

Tue, 22 Mar 2016 19:11:07 -0400

According to a recent study, underground species of army ants are much less tolerant of high temperatures than aboveground ants. Credit: Kaitlin Baudier.

Army ants, which move in swarms and show their prey little mercy, are some of the most ferocious insects in the animal kingdom, but a recent study reveals a weakness in some underground species: warm temperatures.

Travels in Geology: Gotland getaway: Sweden's 'tropical' escape in the Baltic

Wed, 16 Mar 2016 19:46:07 -0400

The iconic sea stacks, called raukarna, of Langhammars Nature Reserve on Fårö Island are the remnants of Silurian coral reefs. Credit: Naomi Lubick.

White sand beaches and thatched-roof houses probably are not part of most people’s conception of Sweden, yet they are characteristic of this northern European nation’s very own coral reef island getaway. This is no tropical island, mind you: 3,100-plus-square-kilometer Gotland sits squarely in the Baltic Sea, off the southeastern shore of Sweden just a short trip from the capital, Stockholm. My husband and I had heard about Gotland since we moved to Sweden several years ago. Swedes extol their country’s largest island as a place with good food, great beaches and lovely summers.

The ups and downs of an island

Wed, 16 Mar 2016 18:54:42 -0400

The approximate amount of uplift of Chile's Isla Santa Mariá resulting from the 2010 Maule earthquake is evident here from the ring of dead seaweed near the base of the rock. Credit: Daniel Melnick.

In 1835, Captain Robert FitzRoy and the crew of the HMS Beagle — who were exploring and studying the Chilean coast with Charles Darwin in tow — arrived at Isla Santa Mariá near the city of Concepción six weeks after a magnitude-8.5 earthquake jolted the region. Along with scenes of dried seaweed and dead mussels lining the island’s shores well above the high-tide line, comparison of a bathymetric survey of a shallow bay adjacent to Santa Mariá to one conducted the previous year suggested to FitzRoy that the earthquake had thrust the island 2.4 to 3 meters out of the water.

Geologic Column: Blockbuster solutions

Sun, 13 Mar 2016 17:04:46 -0400

LED light array. Credit: Copyright Shutterstock.com/Asharkyu

I see a lot of movies. By “a lot,” I mean about 250 per year. Since retiring, one of the activities my wife, Claudia, and I have enjoyed is traveling around the U.S. attending film festivals. When you see as many movies as we do, you tend to forget most of them. Occasionally, though, one sticks with you. Such is the case with “The Imitation Game.” The 2014 film recreated the innovative efforts of British scientists, led by Alan Turing, to cleverly reverse-engineer the Enigma cipher machine used by the Axis powers in World War II and break their secret codes. The film dramatically illustrated how novel ways of evaluating or explaining data can reveal new answers. It reminded me of how science makes leaps forward when practitioners take unconventional steps. This happened repeatedly in geology in the 1960s and ‘70s.

Down to Earth With: Glaciologist Ted Scambos

Thu, 10 Mar 2016 18:53:47 -0500

Ted Scambos. Credit: NSIDC, University of Colorado.

As a young boy, Ted Scambos was fascinated by space and technology, and spent many hours watching aircraft take off and land at the Air Force bases where his father, a pilot, was stationed. For his birthday or Christmas, he says he would often ask for a new telescope or a book about the planets. By sixth grade, Scambos had decided to become an astronomer. But by high school, his attention shifted from outer space to chemistry, and he set up an elaborate chemistry set in his parents’ basement. As Scambos’ interests evolved, he gradually realized that although astronomy and chemistry were both very hands-on disciplines at first, the deeper he delved, the more esoteric they became. Instead, he found himself drawn to geology, especially after discovering how much he enjoyed fieldwork.

Comment: How 'Frankenstein' prevents us from tackling climate change

Thu, 03 Mar 2016 19:53:18 -0500

Krakatau volcano in Indonesia. Credit: iStock.com/Oystein Lund Andersen

Just over two hundred years ago, on the Indonesian island of Sumbawa, Mount Tambora erupted with an explosive plume that ejected debris up to 43 kilometers into the atmosphere, darkening daytime skies. Molten rock and pyroclastic flows cascaded down the volcano’s flanks as ash spread out over hundreds of thousands of square kilometers. This was the most powerful volcanic eruption of the past 500 years. Tsunamis surged. Tens of thousands of people died directly from the eruption, with hundreds of thousands more dying in its aftermath from the starvation and disease that followed widespread crop failures.

Himalayas get a new birthdate

Wed, 02 Mar 2016 18:54:14 -0500

By dating crust that broke off during the initial collision between India and Eurasia, scientists have been able to pinpoint the birthdate of the Himalayas for the first time. Credit: University of Sydney

The Himalayas are the highest and widest mountain range on the planet, but when they began forming has never been clear. In a new study, researchers have now pinpointed the date of the initial collision between India and Eurasia that led to the birth of the Himalayas.

Geomedia: Books: The danger of anti-data ideologies is explored in 'Denying Science'

Mon, 29 Feb 2016 17:48:09 -0500

"Denying Science," by John Grant, Prometheus Books, 2011. ISBN: 978-1616143992

I see science denialism as a pernicious problem in modern society. It was with some anticipation, then, that I recently read John Grant’s 2011 book “Denying Science.” In it, I found a mix of indignation and new information, as well as a lot with which I was already familiar.

Travels in Geology: The King's Highway: The crossroads of ancient Jordan

Mon, 29 Feb 2016 14:35:08 -0500

The King's Highway offers travelers dramatic scenery and a chance to follow an ancient trade route used by many civilizations. Credit: Terri Cook and Lon Abbott.

The King’s Highway, a Middle Eastern thoroughfare that once stretched from Egypt to the Euphrates River, has been used by numerous civilizations over the last few thousand years. Since the Iron Age, this storied path has served as a vital trade route along the north-south spine of a narrow plateau cutting through the center of Jordan. A trip along the King’s Highway in Jordan today offers breathtaking scenery, world-class geologic features, surprisingly few tourists, and the chance to walk in the historic footsteps of people from Nabataean traders transporting frankincense to Petra, to descendants of Abraham traveling to the Promised Land, to Crusaders, Christian and Muslim pilgrims, and even Roman legions marching across the empire’s desert frontier. Each civilization has left its mark on this raw landscape, creating a cultural crossroads that offers an unforgettable journey through human and Earth history.

Getting there and getting around Jordan

Mon, 29 Feb 2016 13:35:28 -0500

For an experience like no other, spend a night or two off the grid in a Bedouin goat-hair tent in the heart of Wadi Rum. Credit: both: Terri Cook and Lon Abbott

Jordan has two international airports: Amman and Aqaba. Amman’s Queen Alia International Airport is the main gateway, offering service to most major Middle Eastern and European cities and regular nonstop flights to New York, Chicago and Montreal. The airport is located 35 kilometers south of Amman; reach the city via express bus service or taxi. Taxis also serve Madaba, which is much smaller and closer to the airport. Madaba hotels will arrange airport pickup and King’s Highway transportation for you. The most convenient and flexible exploration option is with your own vehicle. Several rental agencies operate in Madaba, with more selection at the airport. Our vehicle was delivered to our Madaba hotel, allowing us to avoid city driving in Amman. Signs are generally in both Arabic and English.

Volcanic aerosols not enough to cause mass extinctions?

Fri, 19 Feb 2016 18:35:29 -0500

Fresh basaltic lava degasses in the Holuhraun lava field in January 2015. The months-long Holuhraun eruption is a modern analog, albeit on a much smaller scale, of ancient flood basalt eruptions. Credit: Anja Schmidt, University of Leeds.

Mass extinctions — when more than half of Earth’s species disappear in a geologic instant — offer some of the planet’s most perplexing unsolved mysteries. Prolonged periods of volcanic activity have long been prime suspects for these ancient whodunits, the most recent of which finished off the last nonavian dinosaurs at the close of the Cretaceous about 66 million years ago. But scientists debate how drastic the environmental effects of such volcanism might have been, and whether other factors — like asteroid impacts, as in the end-Cretaceous extinction — played a big role as well.

Uranium contamination in aquifers could be linked to nitrate

Tue, 16 Feb 2016 10:49:05 -0500

Uranium (red) and nitrate (blue) levels in groundwater are indicated at sites across the U.S. in this map, including in the Central Valley (California) and High Plains (central U.S.) aquifers. Credit: University of Nebraska--Lincoln

Nitrogen is an essential nutrient for plant life, but plants can only take up so much so fast. When excess nitrogen enters the environment by way of fertilizer and manure runoff, as well as in automobile and industrial emissions, it becomes a pollutant that can leach into waterways, carrying with it unintended — and often undesirable — consequences. In a new study, researchers have found evidence of one such consequence: elevated uranium levels in two major U.S. aquifers.

Volcanic eruptions affect rivers around the world

Tue, 09 Feb 2016 09:05:26 -0500

Large volcanic eruptions, like the 1991 eruption of Mount Pinatubo in the Philippines, can affect river flow rates around the world. Credit: Dave Harlow, U.S. Geological Survey.

Volcanic eruptions are some of the most powerful agents of climate change on the planet, with some very large events impacting global weather for up to a decade after an eruption. A new study highlights some of the indirect effects of large eruptions, such as how they impact rivers around the world.

Siwash Rock as an urban geoheritage icon

Mon, 08 Feb 2016 15:18:22 -0500

Cliffs on the north side of Stanley Park in Vancouver, B.C., expose mafic dikes and an overlying flow or shallow sill cross-cutting Cretaceous sandstones. The intrusives, dated to 31.5 million years ago, range from basalt to andesite. At Prospect Point near Lions Gate Bridge, strong polygonal jointing varies from horizontal to vertical, resembling stacked cordwood at the base with columns above. Siwash Rock, a sea stack, was isolated when wave action eroded away the surrounding sandstone and jointed intrusives of a former rocky point. Credit: both: Lionel Jackson.

Siwash Rock in Stanley Park, Vancouver, British Columbia, is a prominent and photogenic sea stack — an erosional remnant of an Oligocene basalt dike that cuts through Cretaceous sandstones. The rock (properly named “Slahkayulsh,” meaning “he is standing up”) is a geoheritage locality in both aboriginal and nonaboriginal iconography.

Urban type sections

Mon, 08 Feb 2016 15:12:38 -0500

Gravel pits (the wall here is 100 meters tall) on the Coquitlam River in Coquitlam in Metro Vancouver. This important geological exposure of alluvium and glacial tills comprises a nonglacial-to-glacial cycle and is a scientifically important reference section. Its continued existence is threatened by encroaching development and varied public concerns. Complex and often conflicting concerns are typical for urban geological sites. Credit: Michael Wilson.

It might surprise people to learn that some type sections can be found in cities. Type sites require conservation and protection. An example from the Vancouver metro area in British Columbia is a series of gravel pits along the Coquitlam River that are the type section for deposits associated with the Coquitlam glacial stade. The pits, which we visited as part of our field trip at the Geological Society of America meeting in Vancouver in 2014, have been a focus of public concern over issues ranging from aesthetics to the delivery of sediment to a nearby salmon stream; yet they have also been of vital economic importance in supplying raw material to a growing metropolis.

Urban geology: An emerging discipline in an increasingly urbanized world

Mon, 08 Feb 2016 13:06:37 -0500

At Marshall's Beach south of the Golden Gate Bridge in San Francisco, the Franciscan mélange is exposed. During last year's annual meeting of the American Geophysical Union in San Francisco, geologist Callan Bentley and others visited the site to photograph the rocks. Credit: Callan Bentley.

The mass urbanization of the human race is a relatively new phenomenon in the history of civilization. In 1900, when geology was maturing as a science, only 10 percent of the global population lived in urban settings; now, this proportion has surpassed 50 percent, fed by both overall population growth and rural-to-urban migration. And by 2030, it is expected to reach 60 percent. The United States reached 50 percent urbanization around 1930 and is now approaching 70 percent. The urban population of Canada, meanwhile, accounts for about 80 percent of the country’s people. Ten urban areas around the world now exceed 20 million people, with the Tokyo metropolitan area approaching 35 million — larger than the populations of most countries.

Fire-fountain carbon sheds light on lunar origins

Tue, 02 Feb 2016 14:42:31 -0500

Tiny inclusions of lunar magma, such as this one, trapped inside olivine crystals offer clues to the composition and origins of the moon. Credit: Saal Lab/Brown University

The moon was once thought to be virtually devoid of water and other volatile materials — a presumed consequence of extreme heating during its formation. But a recent study of lunar volcanic glasses, from samples brought back by the Apollo 15 and 17 missions, is adding to the growing stack of recent evidence suggesting the moon is not the volatile-free place scientists once suspected. The findings bring us one step closer to understanding the moon’s origins.

Down to Earth With: Yosemite's first park geologist Greg Stock

Tue, 02 Feb 2016 10:02:41 -0500

Stock and U.S. Geological Survey civil engineer Brian Collins download data to study how daily temperature variations affect granitic exfoliation prior to rockfalls. Credit: USGS/Valerie Zimmer.

A love of rock climbing led Yosemite National Park geologist Greg Stock, seen here on a cliff face at Glacier Point in Yosemite, into the field of geomorphology. Credit: Steven Bumgardner.

As a child growing up in the foothills of California’s Sierra Nevada Mountains, Greg Stock and his family took frequent trips to Yosemite National Park. One of his first memories is of hearing and seeing a giant rockfall tumble down the face of El Capitán. Today, Stock studies such rockfalls and how they impact safety in the area as the first park geologist employed at Yosemite.

Geomedia: Apps: Join the crowd: Introducing a new generation of geo-apps

Mon, 01 Feb 2016 15:06:44 -0500

A new app uses smartphones to detect cosmic rays. Credit: Crayfis.io.

At a time when the technical and computing capabilities of science are evolving at breakneck speeds, it might seem like researchers would always seek out more powerful and sophisticated tools to tackle their scientific questions. But some have chosen the opposite strategy: drawing on the dispersed resource of millions of relatively low-tech devices like smartphones and personal computers — and their users.

Getting there and getting around Kentucky's Red River Gorge

Mon, 01 Feb 2016 13:39:53 -0500

Fireflies illuminate the evening sky above tents at Miguel's Pizza (right), a great place to camp while exploring the Red River Gorge. Credit: both: Alex Mandrila

Entry to Daniel Boone National Forest and the Red River Gorge is free. The nearest airports are in Lexington and Louisville, Ky., both about an hour away by car. Cincinnati is two hours away. Having a car is a must for getting to and driving around the Red.

Miguel, and trad versus sport climbing

Mon, 01 Feb 2016 13:33:54 -0500

Miguel Ventura of Miguel's Pizza, preparing pizza dough. Credit: Alex Mandrila.

Miguel Ventura, owner of Miguel’s Pizza, has been at the Red River Gorge Geological Area (“the Red”) since 1984. He started selling ice cream to tourists, and then started making pizza, which he prepares from scratch in his garage near the main store.

Travels in Geology: Rocks and Climbing at Kentucky's Red River Gorge

Fri, 22 Jan 2016 10:11:13 -0500

A climber hangs from plate-like sandstone protrusions at the Pendergrass- Murray Recreational Preserve. Credit: Alex Mandrila.

One Friday last June, some friends and I drove five hours from Ann Arbor, Mich., to Kentucky’s Red River Gorge, a natural scenic area also called “the Red.” By the time we hit Dayton, Ohio, rain clacked against the car windows, and lightning flashed. We continued on, and at about 2 a.m., southeast of Lexington, Ky., we turned onto Highway 11, part of the Red River Gorge Scenic Byway. This 75-kilometer stretch along Highways 11, 715 and 77 loops visitors through the Red River Gorge Geological Area in Daniel Boone National Forest — which features more than 100 natural sandstone arches — as well as Natural Bridge State Resort Park and the Clifty Wilderness.

Ice (Re)Cap: February 2016

Fri, 15 Jan 2016 08:33:28 -0500

Based on a study of New Zealand's Franz Josef Glacier, researchers have developed a novel numerical law to describe glacial erosion rates on Earth. Credit: Frédéric Herman.

UNESCO adopts Global Geoparks Program

Fri, 15 Jan 2016 08:13:53 -0500

Together with the Burren, the striking Cliffs of Moher on the Republic of Ireland's west coast were first designated a Global Geopark in 2011. Credit: Terri Cook and Lon Abbott.

On Tuesday, Nov. 17, 2015, the 195 member states of UNESCO formally adopted the Global Geoparks Network, designating the inscribed parks as UNESCO sites during the organization’s 38th General Conference in Paris.

D.C. wastewater no longer going to waste

Thu, 14 Jan 2016 11:16:45 -0500

In 2015, D.C. Water, which treats wastewater from Washington, D.C., and the Maryland and Virginia suburbs, began using a thermal hydrolysis treatment system to convert sewage into electricity. Credit: D.C. Water.

D.C. Water & Sewer Authority, which treats sewage from Washington, D.C., as well as from the Maryland and Virginia suburbs ringing the city, is the biggest consumer of electricity in the U.S. capital. But last September, D.C. Water began creating its own power, becoming the first utility in the country to convert sewage into electricity.

Getting there and getting around peninsular Greece

Mon, 11 Jan 2016 11:02:23 -0500

The staging spot for the two-day ascent of Olympus is the quaint village of Litochoro. From there, visitors drive to Prionia (above), where they start hiking. The trail leads through gorgeous scenery for 6 kilometers up to a well-appointed hut (left), which serves up heaping plates of pasta, bowls of hearty soup and steaming mugs of cocoa, and where people usually spend the night before summiting Olympus. Credit: both: Terri Cook and Lon Abbott.

Northern Greece has two major airports: Athens and Thessaloniki. Athens International Airport offers the most options, including seasonal daily nonstop flights from New York, Philadelphia and Montreal, as well as flights to most European cities.

Travels in Geology: Peninsular Greece: A gorgeous state of collapse

Mon, 11 Jan 2016 10:05:34 -0500

Although many visitors head to Greece to visit the islands and Athens, peninsular Greece has many incredible sights to see as well, including (clockwise from top left) the ruins of Delphi, home of antiquity's most famous oracle; the Acropolis; the unfathomable monasteries in Meteora; and Mount Olympus, the legendary home of the 12 Olympian gods and goddesses. Credit: all: Terri Cook and Lon Abbott.

The night before we were scheduled to fly to Athens last summer, the Greek government indefinitely closed the country’s banks and imposed strict capital controls, including limitations on ATM withdrawals and credit card use, to prevent the collapse of their banking system. The evening news led with images of panicked tourists hoping they could withdraw enough money to pay for their hotel before the cash ran out.

Benitoite: A rare gemstone

Mon, 11 Jan 2016 08:57:25 -0500

Gem-quality specimens of benitoite, California's state gemstone, are found only in San Benito County where Pinnacles National Park is located. Credit: Didier Descouens, CC BY-SA 4.0.

The tectonic forces that formed Pinnacles also helped form one of the world’s rarest gemstones: benitoite. Gem-quality specimens are only found in San Benito County where Pinnacles National Park is located. Benitoite, which is California’s state gemstone, has a deep azure color, a pyramidal crystal habit, and a light-blue fluorescence under ultraviolet light.

Atmosphere, more than ocean, might drive Atlantic climate variation

Fri, 08 Jan 2016 08:10:00 -0500

Hurricane Isabel was photographed from the International Space Station in 2003, during the most recent warm phase of the Atlantic Multidecadal Oscillation (AMO). The AMO, which seems to affect the frequency of tropical storms, may be more affected by atmospheric circulation than by the ocean. Credit: NASA.

Atmospheric, not oceanic, circulation may be the main driver of climate variations over the North Atlantic Ocean, potentially complicating future hurricane and drought predictions, according to the authors of a new study.

Irrigation drives rain away in East Africa

Thu, 07 Jan 2016 11:31:33 -0500

Croplands in the Gezira Scheme in Sudan, near the confluence of the Blue Nile and White Nile, are watered by a vast network of irrigation canals. Credit: NASA.

Researchers have found that large-scale agricultural irrigation, intended to supplement precipitation, may actually drive rainfall away, potentially exacerbating conditions in some areas while improving them in nonirrigated lands.

How deep do the Alps go?

Thu, 07 Jan 2016 11:18:43 -0500

The mountains of the Dora Maira Massif, part of the Western Alps, surround the Maira Valley in northwestern Italy. Seismic data collected in the region suggests that, far below the massif, the buoyant continental crust of the Eurasian Plate is diving under the Adriatic Plate. Credit: Archenzo, CC BY-SA 3.0.

Continental crust was long thought to be too buoyant to subduct into the mantle, unlike denser oceanic crust, which descends into the mantle in many locations around the world. But the discovery of coesite — a type of silica formed at the extreme pressures present in subduction zones — in the Alps in 1984 challenged that long-held idea. Seismic evidence backing up claims that continental crust has indeed been subducted beneath the Alps has been scant, however, until now.

Land plants came prepared for terrestrial life

Thu, 07 Jan 2016 10:54:54 -0500

Nitella hyalina is a stonewort and a member of the charophyte green algae family. No known charophyte alga has symbiotic associations with mycorrhizal fungi, but N. hyalina and other stoneworts do develop root-like rhizoids that anchor the thallus in sand and mud, and probably frequently interact with fungi. The frame is about 5 millimeters tall. Credit: Charles F. Delwiche, University of Maryland, all rights reserved.

Plants colonized land between 450 million and 420 million years ago, and, once there, they drastically altered terrestrial landscapes and provided resources for animals leaving the oceans around the same time. One adaptation that helped plants gain a foothold on land is a symbiosis with fungi known as arbuscular mycorrhizae (AM), which help plants acquire water and key nutrients from the soil and are still associated with most land plants today. In return, plants provide the fungi with bioavailable carbon produced during photosynthesis. When this symbiosis evolved has remained unclear, but researchers recently discovered that it likely has roots in a group of freshwater algae ancestral to land plants.

Permian-Triassic extinctions timed differently on land and at sea

Thu, 31 Dec 2015 13:25:43 -0500

Sandstones and volcanic deposits at Old Lootsberg Pass in South Africa's Eastern Cape Province preserve fossil and geochronometric evidence suggesting that the Permian-Triassic terrestrial and marine extinctions were not simultaneous. Credit: Robert A. Gastaldo.

Life on land and in the sea was nearly eradicated about 252 million years ago in the largest-known mass extinction. The cataclysm, known as the Permian-Triassic (P-T) mass extinction, was likely driven by extensive flood basalt volcanism in Siberia and is thought to have affected global biodiversity simultaneously. However, based on analyses of rocks deposited around the time of the P-T boundary in the Karoo Basin of South Africa, scientists suggest in a new study that the terrestrial turnover in vertebrates occurred earlier than the marine extinction. If true, a second trigger — other than Siberian volcanism — might need to have occurred to explain both events.

Impact or eruptions: Are both to blame in the great end-Cretaceous whodunit?

Thu, 31 Dec 2015 11:02:00 -0500

The mountains of basalt that remain hint at the scale of volcanism that heaped massive amounts of lava onto the Indian subcontinent around the time of the Cretaceous-Paleogene transition. Credit: Blair Schoene.

The Deccan Traps sprawl over more than half a million square kilometers of India. Credit: K. Cantner, AGI.

Few episodes in geologic history are as widely recognized as the Cretaceous-Paleogene, or K-Pg, boundary 66 million years ago. Utter “K-Pg,” “K-T” (for Cretaceous-Tertiary, as it’s still commonly known) or “end-Cretaceous” to any geoscientist and you’re virtually assured of a knowing glance as he or she recalls at least the textbook basics of a large bolide impact and mass extinction that finished off the dinosaurs and gave rise to the Age of Mammals. Mention it to science-interested laymen, meanwhile, and they may conjure images of tyrannosaurs peering over their shoulders in anguish as they flee from streaking meteors.

How to feed 11 billion people: Addressing the 21st century's biggest challenge

Wed, 30 Dec 2015 10:03:38 -0500

A market in Delhi, India. Credit: Christian Haugen, CC BY 2.0.

In April 2008, violent protests erupted across the impoverished Caribbean nation of Haiti. Enraged by soaring food prices and all-too-frequent hunger pangs, protesters smashed windows, looted shops, barricaded streets with blazing cars and stormed the presidential palace in the capital, Port-au-Prince. The week of violence, during which five people were killed, flared after the cost of staples like beans and cooking oil spiked dramatically and the price of rice nearly doubled in four months, increasing hardships in a nation where 80 percent of the population survives on less than $2 per day.

Geologic Column: Decades later, Mr. Keene's earth science class sticks with me

Tue, 29 Dec 2015 09:21:12 -0500

Staten Island's Curtis High School. Credit: Sweepditrack, CC BY-SA 3.0.

My earth science class at Staten Island’s Curtis High School in 1959 presented a dilemma for me: My teacher, Mr. Melvin Keene, had a great sense of humor and made the subject easy to understand, but he was also a neighbor and a friend of my dad’s.

Benchmarks: January 10, 2013: Pinnacles National Park is founded

Tue, 29 Dec 2015 08:51:27 -0500

Pinnacles National Park is famous for its volcanic rock spires. Credit: Lucas Joel.

The new entrance sign on Pinnacles National Park's eastern side. Credit: Lucas Joel.

On Jan. 10, 2013, when President Barack Obama signed legislation granting national park status to the former Pinnacles National Monument — designated as such by President Theodore Roosevelt in 1908 — the land became the country’s 59th national park. Tucked away in California’s Coast Ranges about an hour’s drive inland from Big Sur, Pinnacles covers almost 11,000 hectares of wilderness near Paicines, Calif., and is one of the main refuges for the critically endangered California condor, which nearly went extinct in the 1980s. Recently, with conservation programs like the one that exists at Pinnacles, the birds are on their way toward recovery.

Energy Notes: June 2014 - 2015

Sun, 27 Dec 2015 14:58:25 -0500

Credit: The American Geoscience Institute

U.S. Oil & Petroleum Imports (million of barrels per day)

Oil and petroleum imports data are preliminary numbers taken from the American Petroleum Institute’s Monthly Statistical Report. For more information visit www.api.org.

Mineral Resource of the Month: Iron and Steel Slag

Sun, 27 Dec 2015 14:54:14 -0500

Hendrik G. van Oss, a mineral commodity specialist for the U.S. Geological Survey’s National Minerals Information Center, compiled the following information on ferrous slag, which has a number of uses in construction.

Tapping the slag at a blast furnace in Pittsburgh, Pa., 1938. Credit: Library of Congress.

Iron and steel slag, also known as ferrous slag, is produced by adding limestone (or dolomite), lime and silica sand to blast furnaces and steel furnaces to strip impurities from iron ore, scrap and other ferrous feed materials and to lower the heat requirements of the iron- and steelmaking processes. Ferrous slag forms as a dominantly calcium silicate melt that floats on top of the molten crude iron or steel; the slag is then removed from the liquid metal.

Sierra Nevada snowpack lowest in 500 years

Wed, 23 Dec 2015 13:15:15 -0500

A side-by-side comparison of satellite views over the Sierra Nevada shows the dramatically smaller amount of snow cover in late March 2015 (right) compared to 2010. Credit: NASA/MODIS.

With several ski resorts closing early last winter in California’s Sierra Nevada Mountains due to lack of snow, many people suspected the snowpack for the year was on the low side. This suspicion has been confirmed: Snow levels for the winter of 2014–2015 registered as the lowest in the last 500 years.

Oceanographers solve mysterious beach explosion

Wed, 23 Dec 2015 12:40:06 -0500

University of Rhode Island researchers collected sediment cores at the site of a mysterious explosion that injured a woman at Salty Brine State Beach in Narragansett, R.I., in July 2015. Credit: Chris Deacutis.

Late on the morning of Saturday, July 11, 2015, Kathleen Danise, a 60-year-old nurse and grandmother from Waterbury, Conn., was enjoying a sunny day at Salty Brine State Beach on the shores of Block Island Sound in Narragansett, R.I., when an explosion knocked her from her beach chair. She landed a few meters away near a rock jetty, unconscious and suffering a concussion, two fractured ribs and bruising for which she was hospitalized overnight.

Sunlight liberates nitrogen from urban grime

Fri, 18 Dec 2015 09:46:09 -0500

Urban grime, as seen here in Manchester, England, is a mixture of thousands of chemical compounds. Credit: Pete Birkinshaw, CC by 2.0.

Cities are dirty. That’s obvious from all the grime that collects on glass, metal and other urban surfaces. But new research shows that not everything in that grunge is staying put at ground level, and that the grime — and the nitrogen in it — is contributing to air pollution in ways scientists aren’t accounting for.

Midwest's hybrid rift formed in three stages

Thu, 17 Dec 2015 11:44:56 -0500

Many of the rocks exposed around Lake Superior were uplifted from the Midcontinent Rift during the formation of Rodinia, including these basalt cliffs along the Porcupine Escarpment in Michigan's Upper Peninsula. Credit: Mary Caperton Morton.

Middle America is not often recognized for its interesting geology, yet it boasts one of the largest and most unusual geologic features in the country: the Midcontinent Rift, which stretches 3,200 kilometers in two arms from Lake Superior to Oklahoma and Alabama. Subsurface imaging of the rift has revealed that it’s not just a rift, it’s also what’s known as a large igneous province, making it a hybrid geologic feature not seen anywhere else in the world. A new modeling study is offering a more complete story of how the Midcontinent Rift evolved, in three stages.

Down to Earth With: GEO Secretariat Director Barbara Ryan

Thu, 17 Dec 2015 11:06:47 -0500

Barbara Ryan is in her second term as the secretariat director of the Group on Earth Observations (GEO). Credit: U.S. Mission Geneva.

When Barbara Ryan enrolled as a freshman at the State University of New York in Cortland, she enjoyed athletics so much that she planned to pursue a career in physical education and coaching. Then her roommate convinced her to take a class in paleontology. She was hooked, and within months Ryan changed her major to geology, launching herself down an entirely different path.

Is aviation 'whitening' the sky?

Wed, 16 Dec 2015 21:55:56 -0500

Clear blue skies may not be as clear as they appear. Skies are actually becoming less clear, causing incoming sunlight to scatter in different directions, rather than striking the planet directly — and aviation may be to blame, according to research presented this week at the fall meeting of the American Geophysical Union (AGU) in San Francisco.

Subseafloor biosphere extended to greatest depth yet

Tue, 15 Dec 2015 10:38:45 -0500

Microbes cultured from a coal seam buried 2 kilometers below the seafloor off Japan are seen in this scanning electron microscope image at 5,000-times magnification. Credit: Hiroyuki Imachi, JAMSTEC.

Scientists studying sediments collected from the deepest scientific borehole ever drilled have found microorganisms living at astounding depths beneath the seafloor. Recent studies have previously found bacteria and archaea scratching out meager livings in marine sediments buried as deep as 1.9 kilometers, but the new find extends the known biosphere even farther down.

Magnetic field around since Hadean

Tue, 15 Dec 2015 10:33:01 -0500

Earth's magnetic field, which shields the planet from most high-energy solar radiation, could be 4.2 billion years old, far older than previously recognized. Credit: Michael Osadciw/University of Rochester.

Earth’s magnetic field might have been shielding the planet from solar radiation and contributing to its habitability 770 million years earlier than previously recognized, according to a new study in Science.

Ancient African villages shed light on Earth's magnetic field

Mon, 14 Dec 2015 10:11:43 -0500

Grain bins, such as these modern examples in South Africa, were burned in drought rituals during the Iron Age in Africa. The scorched earth beneath the structures has preserved rare clues about Earth's magnetic field 1,000 years ago. Credit: John Tarduno/University of Rochester.

Throughout Earth’s history, the planet’s magnetic field has changed polarity hundreds of times, with the magnetic north and south poles swapping positions. These reversals sometimes occur every few thousand years, or after hundreds of thousands of years. The last known magnetic reversal took place nearly 800,000 years ago, leaving many to wonder if we’re overdue for a reversal. Now, research from southern Africa, an understudied region, analyzing magnetized minerals preserved in the charred floors of 1,000-year-old torched huts has shed light on geomagnetic patterns that may indicate — or perhaps even trigger — such a switch.

Lake sediments suggest mild volcanic winter after massive Toba eruption

Mon, 14 Dec 2015 10:02:39 -0500

Lake-floor sediments from Lake Malawi in East Africa appear to show no sign of a widespread volcanic winter following the Toba super-eruption 74,000 years ago, according to a new study. Credit: Traveling Otter, CC BY-SA 2.0.

Roughly 74,000 years ago, the largest volcanic eruption of at least the last 2.5 million years — and possibly the last 27 million years — spewed as much as 5,000 cubic kilometers of magma and ash, the latter of which spread far and wide from the source. This catastrophic eruption of the Toba supervolcano on the Indonesian island of Sumatra has long been suggested as a trigger for a precipitous period of global cooling known as a “volcanic winter” that in turn might have driven early humans to the brink of extinction. In a new study, researchers dispute these notions, concluding from an analysis of climate-sensitive microfossils preserved in lake sediments in East Africa — the ancestral home of early humans — that the region experienced little or no cooling following the massive eruption.

What lies below?

Mon, 14 Dec 2015 09:17:19 -0500

Scientists using a new tomographic model of Earth's mantle have identified 5,000-kilometer-wide swells of potentially hot material in the lower mantle that the researchers say confirm the existence of plumes. Credit: French and Romanowicz, Nature, 2015.

Technological advances continue to improve the resolution of our view of Earth’s interior, but disagreement remains over what we’re viewing. In a recent Nature paper titled, “Broad plumes rooted at the base of the Earth’s mantle beneath major hot spots,” Scott French, a computational scientist at the Department of Energy’s National Energy Research Scientific Computing Center at Lawrence Berkeley National Laboratory, and Barbara Romanowicz, a seismologist at the University of California at Berkeley, reported the development of the most detailed model yet of the structure of the mantle.

The question of mantle plumes

Mon, 14 Dec 2015 08:49:28 -0500

Over the years, many different locations have been proposed as hot spots. Some of the most well-known proposed sites are labeled with red dots in this diagram, which also depicts the borders of Earth's tectonic plates. Credit: K. Cantner, AGI.

In 1963, J. Tuzo Wilson first proposed that volcanic chains like the Hawaiian Islands form when a tectonic plate drifts over a “hot spot” in the mantle. Eight years later, Princeton geophysicist W. Jason Morgan suggested that such hot spots — he initially proposed about 20 around the world — were fueled by narrow plumes of hot mantle rock rising from the core-mantle boundary.

Comment: GSW: A celebrated society celebrates its 1,500th meeting

Wed, 09 Dec 2015 10:23:53 -0500

GSW has met at the Cosmos Club in Washington, D.C., since 1893. Credit: Agnostic Preachers Kid, CC BY-SA 3.0.

The GSW gavel. Credit: Callan Bentley.

I tucked in my shirt as I walked up the front steps of the stately mansion that houses the Cosmos Club on Massachusetts Avenue in Washington, D.C. At the top, I tentatively opened the massive wrought-iron door. The warmly lit interior came into view, and I crossed the threshold.

Benchmarks: August 1975: Geotimes magazine inspires name of rock formation: A Q&A with Tony Alabaster

Fri, 20 Nov 2015 10:58:02 -0500

The pillow lavas pictured here on the cover of the August 1975 issue of Geotimes magazine were later named the Geotimes unit after the magazine. Credit: AGI.

In August 1975, an intriguing rock formation in Oman appeared on the cover of Geotimes magazine, EARTH magazine’s predecessor. This pillow lava — a type of rock that forms when hot molten basalt flows into water, such as happens in Hawaii, or erupts underwater — is one of the lowermost units of the now-famous Semail ophiolite sequence. Ophiolites, pieces of ancient oceanic crust and upper mantle later uplifted and exposed on land, were a hot geological topic in the 1970s, because they helped illuminate the process of seafloor spreading, a key puzzle piece supporting the then-revolutionary theories of continental drift and plate tectonics.

Benchmarks: August 2, 1922: Marines invade Teapot Dome, deepen scandal

Fri, 20 Nov 2015 10:24:46 -0500

Teapot Dome in Wyoming today and in 1927 (inset). Credit: both: courtesy of the U.S. Department of Energy.

On Aug. 2, 1922, U.S. marines took over the oilfields at Teapot Dome. Credit: courtesy of the U.S. Department of Energy.

Early in the morning of Aug. 2, 1922, soldiers from the United States Marine Corps arrived at the train station in Casper, Wyo. They had been traveling for three days from the East Coast to reach an important government facility, officially designated the Naval Petroleum Reserve No. 3 (NPR-3), better known as Teapot Dome. Their orders, which President Warren Harding had approved only the week before, were to evict trespassers from a small oil claim in the northern end of the reserve. Following a quick breakfast, the soldiers proceeded north by car under the command of Capt. George K. Shuler. He had hand-picked the men, with whom he had fought in World War I.

Getting there and getting around Sedona

Fri, 20 Nov 2015 08:49:12 -0500

Sedona is home to dozens of art galleries. Credit: Don Graham, CC BY-SA 2.0.

Montezuma Castle in the Verde Valley is one of North America's best-preserved Sinaguan cliff dwellings. Credit: Terri Cook and Lon Abbott.

Although Flagstaff’s Pulliam Airport is located just 40 kilometers from Sedona, flights into Phoenix Sky Harbor International Airport, a two-hour drive to the south, are usually cheaper and have better connections. It is also possible to ride Amtrak’s Southwest Chief route to Flagstaff. To fully explore central Arizona, you will need a car; if you fly in, you can rent one at either city’s airport, in downtown Flagstaff or in Sedona.

Travels in Geology: Sedona: A journey to the edge of a supercontinent

Fri, 20 Nov 2015 08:25:14 -0500

Credit: Tim Watson, CC BY-NC 2.0.

Built upon crimson slopes studded with junipers and towering pines, surrounded by soaring rock spires, and encircled by 800,000 hectares of pristine national forest, the central Arizona town of Sedona is widely recognized for its natural beauty. Sedona is also well known for its diverse recreational opportunities, flourishing art scene and its role as a hub of New Age healing.

Public improvements, private funding

Thu, 19 Nov 2015 11:46:44 -0500

The Denny Hill area shown in 1928 before the final regrade project began and after it was completed in 1931. Credit: courtesy of Seattle Municipal Archives, Image 9331.

Seattle city engineer Reginald H. Thomson may have been the driving force behind the Denny Hill regrades, but they could not have occurred without public support. In order for a regrade to proceed, at least 50 percent of the people who lived in the affected areas had to sign a petition. For example, the Second Avenue regrade needed the signatures of 67 property owners. A completed petition triggered the next phase, which was a city council ordinance that defined the boundaries of the regrade. A second ordinance then provided the funding mechanism, or what was known as a Local Improvement District (LID).

Benchmarks: December 10, 1930: Seattle's Denny Hill disappears

Thu, 19 Nov 2015 11:08:17 -0500

The Washington Hotel in 1905 during the regrade of Second Avenue. Within three years, the hotel and the hill under it had been removed. Credit: courtesy of Seattle Municipal Archives, Image 77282.

Few cities in the United States can rival Seattle for the scale of reengineering to its landscape. Not only did its citizens make more than 890 hectares of new land in its harbor, but they also replumbed the city’s largest lake, completely changing its drainage pattern and drying up its main outlet, and regraded tens of millions of cubic meters of its hills. The most famous of these projects was the elimination of Denny Hill, a 73-meter-high hill that stood at the north end of Seattle’s central business district.

Geomedia: Gifts: Holiday Gift Guide

Thu, 19 Nov 2015 10:35:12 -0500

Science is definitely the new chic, so we’ve tracked down the latest and greatest science accessories and furnishings to help you find the perfect gift for home or office. From agate nightlights to fun science jewelry, this list is sure to have something your science lover will enjoy. Plus, we have some suggestions for great presents for the budding young scientists in your life.

Geomedia: Television: 'NOVA: Making North America' Is Flashy, But Fails on Storytelling

Tue, 17 Nov 2015 15:47:55 -0500

NOVA's Making North America is hosted by paleobotanist Kirk Johnson, director of the Smithsonian.

Geology isn’t often depicted in the popular media, and when it is, the coverage is often related to well-trodden topics like dinosaurs or natural disasters. So when I heard about the new three-hour-long documentary, “NOVA: Making North America,” I hoped for quality storytelling that touched on some of the other fascinating, though less-covered science in the field. The documentary, which has been airing over three consecutive weeks in November, purports to tell the geological, biological and anthropological story of North America. Unfortunately, it falls short on many counts.

Ice (Re)Cap: December 2015

Thu, 12 Nov 2015 10:14:30 -0500

A comprehensive survey of the Greenland Ice Sheet using two decades of ice-penetrating radar data has yielded a three-dimensional view of the internal structure and age of the ice sheet's layers. Credit: NASA's Scientific Visualization Studio.

Balanced boulders in earthquake country highlight interconnected faults

Thu, 12 Nov 2015 10:06:08 -0500

This fragile rock stack in the Grass Valley area of the San Bernardino Mountains in California lies near the San Andreas Fault, one of the most seismically hazardous areas in the United States. Credit: Lisa Grant Ludwig.

Precariously balanced boulders look like bizarre accidents in any landscape, but when they’re found in regions famous for frequent earthquakes, such gravity-defying formations are even more improbable. Scientists have long wondered about an odd collection of dozens of balanced boulders in the San Bernardino Mountains that seemingly should have been toppled centuries ago by the earthquakes that regularly shake Southern California. Even stranger, these car- to house-sized granite boulders are located within 10 kilometers of the active San Andreas and San Jacinto faults. Now, new detective work on 36 of the boulders is giving scientists clues about the connections between these faults.

Chinese cave art reveals record of climate change

Thu, 12 Nov 2015 09:58:36 -0500

An inscription from 1891 found in Dayu Cave (entrance shown above). Credit: both: L. Tan.

In times of drought, Dayu Cave in the Qinling Mountains of central China has remained a reliable source of water, and since at least the 16th century, thirsty visitors to the cave recorded their pilgrimages on the walls. Now the graffiti — rendered in black pigment on the yellow cave walls — is providing scientists with a unique record of how climate change affected nearby communities between 1520 and 1920.

Ocean oxygen levels control seafloor carbon burial

Thu, 12 Nov 2015 09:14:26 -0500

A converted local ferry became a research vessel on Lake Matano in Indonesia, where researchers studied organic carbon from lake-floor sediments. Credit: Sergei Katsev.

Residual organic carbon from dead marine phytoplankton and other oceanic life can follow two pathways: It can be deeply buried in seafloor sediments or it can be oxidized, either in the water column or in shallow sediment layers. The balance between these two processes and the extent of organic carbon burial over time are crucial in the global carbon cycle, but a complete understanding of the factors and rates controlling organic carbon burial versus oxidation in the oceans has been lacking. In a recent study in Geology, scientists improved on an approach to quantify organic carbon oxidation and provided a glimpse of marine organic carbon burial in the Precambrian, when the oceans were anoxic and Earth’s atmosphere was in the early stages of oxygenation.

Human hands not most advanced

Thu, 12 Nov 2015 09:08:44 -0500

With longer fingers, chimpanzees have lower thumb-to-finger-length ratios than humans. Credit: Almécija et al., Nature Communications, 2015, CC BY 4.0.

Compared to chimpanzees, our recent evolutionary cousins, humans have long thumbs relative to our fingers. This trait has endowed our ancestors and us with a particular talent for grasping and working with tools, which likely contributed to our evolutionary success over the last several million years since splitting off from the last common ancestor (LCA) shared by the two groups. But rather than humans having the more evolved hand — a prevailing hypothesis since the late 20th century — a new study suggests that chimps’ hands, with lower thumb-to-finger-length ratios, have changed considerably more.

No laughing matter: Ocean nitrous oxide emissions greater than thought

Thu, 12 Nov 2015 08:46:09 -0500

High productivity ecosystems like the upwelling zone off the coast of Peru, which once supported an abundant anchovy fishery before overfishing collapsed it in the 1970s and ‘80s, also create oxygen minimum zones where high fluxes of nitrous oxide are produced. Credit: ©Shutterstock.com/Sven Schermer.

Nitrous oxide is a potent greenhouse gas and, since the banning of chlorofluorocarbons in 1987, it has become the main driver of ozone loss from the stratosphere. Most atmospheric nitrous oxide is emitted from agricultural land and soils, but roughly a third is thought to come from the ocean. However, marine sources and sinks of the gas are not well understood.

Wormholes may limit landslides

Fri, 06 Nov 2015 13:56:01 -0500

Puerto Rico's Luquillos Mountains appear in this photo taken from the International Space Station in 2007. (Note that north is down in the image.) Credit: NASA

Scientific investigations sometimes take unexpected twists and turns. When Emma Harrison, a graduate student at the University of Pennsylvania, began digging trenches in the mountains of Puerto Rico to study how the soil mantle responds to rapid changes in erosion, she couldn’t help but notice the worms.

Comment: Pipe Dreams: What have we learned from the Volkswagen Clean-Diesel scandal?

Mon, 02 Nov 2015 13:42:36 -0500

In the last couple of years, we both considered buying a Volkswagen. The company’s “clean-diesel” cars offered great fuel economy and were fun to drive. We could go green without sacrificing performance.

Geologic Column: The beginning of "time" as we know it

Mon, 02 Nov 2015 13:33:02 -0500

Pre-Julian Roman calendar found in the ruins of Nero's villa at Antium (Anzio). Credit: Public Domain.

As we approach the end of a year, my thoughts often turn to calendars and the measurement of time. Time is our window on the world; we use it to create order and shape our existence. We use time to measure grand things, like the rise and fall of civilizations, and small things, like the increments of our daily lives.

Solar flare calibration reveals past patterns of volcanism and cooling

Mon, 02 Nov 2015 13:17:45 -0500

Ancient trees, such as this 3,000-year-old Bristlecone Pine in Nevada, maintain records of past temperature changes in their growth rings. Credit: Mary Caperton Morton.

When Mount Pinatubo erupted in the Philippines in 1991, it sent a cloud of ash and sulfuric acid into the atmosphere that blocked incoming solar radiation and caused global temperatures to drop 0.5 degrees Celsius for three years. Quantifying such effects of prehistoric volcanic eruptions on climate, however, has long proved difficult due to inconsistencies in the proxies used to reconstruct atmospheric and temperature fluctuations. In a new study, scientists have used markers left by an unusual solar flare event to align ice-core and tree-ring records, enabling a more accurate accounting of the effects of volcanic eruptions in recent millennia.

Due diligence in river incision data

Mon, 02 Nov 2015 11:40:16 -0500

River terraces near Lees Ferry along the Colorado River between Arizona and Utah record how the river has cut and scoured the surrounding landscape. Credit: Joel Pederson.

As great equalizers of topography, rivers and streams whittle down landscapes by alternately scouring away broad flat swaths of sediment and rock, and incising deeply through them. If a landscape — a mountain range, for example — is being uplifted by tectonic forces, this whittling occurs even faster. River incision rates in particular are thus often used to infer past rates of rock uplift. But determining incision rates themselves is not clear-cut. In a new study in Geology, scientists look at one complicating factor in such calculations, what the authors call the “unappreciated effects of streambed elevation variability” on measuring river incision rates.

Warty algae-like sheets survived Snowball Earth events

Mon, 02 Nov 2015 11:36:31 -0500

Scanning electron microscope images of macroscopic organic warty sheets showing ridges and warts. Scale bars represent 1 millimeter. Credit: Phoebe Cohen.

Between about 730 million and 635 million years ago, during the Cryogenian Period of the Late Proterozoic, Earth is thought to have been almost completely covered in ice twice, events that scientists have termed “Snowball Earth” glaciations. The first global glaciation, the Sturtian, lasted from 730 million to 700 million years ago, and the second, the Marinoan, lasted from 660 million to 635 million years ago. Both glaciations likely put severe limitations on the ability of life — predominately microorganisms — to thrive.

Isotopes could reveal ancient American turquoise trade

Mon, 02 Nov 2015 11:24:21 -0500

Mines in the Halloran Hills of California's San Bernardino County were one location where researchers collected samples of turquoise to study the mineral's lead and strontium isotopic compositions. Credit: Alyson Thibodeau.

For centuries before the arrival of Europeans, turquoise was prized among pre-Hispanic cultures of North America. Caches of the distinctive, creamy-blue-green mineral have been unearthed in crypts and other ritually significant structures in what are now the southwestern United States and northern Mexico. Farther south, in Mesoamerica, archaeologists have found elaborate mosaic masks and ornamentation made of turquoise pieces. Despite multiple anthropological and historical hints, identifying where the turquoise used by different civilizations came from has proven difficult. But in a recent study, scientists have described a geochemical fingerprinting technique that may help parse the geographic origins of turquoise specimens and illuminate trade routes in ancient America.

Opalescent pools shimmer beneath Santorini

Mon, 02 Nov 2015 11:11:00 -0500

Dense carbon dioxide-rich pools on the seafloor near Santorini get their distinctive color from opal particles. The pools may answer questions about deep-sea carbon storage and help scientists monitor the volcano for future eruptions. Credit: Rich Camilli, WHOI.

With its bright blue waters and dramatic cliffside villas, Santorini, Greece, is an idyllic vacation destination, but lurking beneath the Aegean waves lay the remains of one of the most active volcanoes in human history. Because of its eruptive past and proximity to population centers, the Santorini Caldera is closely monitored, but a recent expedition revealed something never before seen there or anywhere else: shimmering opalescent pools of carbon dioxide sequestered on the seafloor.

Gain some, lose some

Tue, 27 Oct 2015 10:36:35 -0400

The magnitude-8.8 earthquake that struck Chile in February increased Earth's rate of rotation by 1.26 millionths of a second. Credit: Both: Thomas Lay/ShelterBox.

Scientists now know that Earth’s rotation is very slowly decelerating, such that the length of the rotational day is about two milliseconds longer than the 86,400 seconds it was nearly two centuries ago. But that doesn’t mean Earth’s rotation is always slowing down. The tidal force of the moon acts to slow Earth’s rotation by taking away some of the planet’s energy. But other factors, such as the expansion and contraction of the atmosphere with the seasons, the churning of material within Earth’s core, and the rebounding of Earth’s surface as the weight of glaciers is removed, can sometimes act to speed up Earth’s rotation by redistributing its mass, thereby altering Earth’s moment of inertia and thus its speed of rotation.

Benchmarks: June 30, 1972: Timekeepers add first "leap second" to clocks

Tue, 27 Oct 2015 10:24:10 -0400

By the early 1960s, astronomers were calculating time based on Earth's orbit around the sun, rather than based on Earth's rotation. Credit: NASA.

English astronomer Edmond Halley was among the first to suspect that the motions of the heavens were not exactly consistent with a notion of a uniform measure of time as indicated by Earth's rotation. Credit: Klaus-Dieter Keller.

On June 30, 1972, at exactly 11:59 p.m. and 60 seconds, timekeepers did something most people only dream about: They added more time to the day.

Benchmarks: May 18, 1952: Stonehenge's age solved with Carbon-14

Mon, 26 Oct 2015 13:33:08 -0400

Stonehenge, towering over England's Salisbury Plain, has long mystified scientists and tourists alike. In 1952, chemist Willard Libby solved one of the monument's most enduring mysteries: its age. Using a brand-new dating technique called radiocarbon dating, Libby determined an age for Stonehenge of about 1848 B.C. Credit: ©iStockphoto.com/Paul Fawcett.

Like sentinels standing guard over a millennia-old secret, the 8-meter-tall stones of Stonehenge rise above the rolling green hills of England’s Salisbury Plain. The origin, date and purpose of the arrangement of the giant standing stones, located about 145 kilometers west of London, have puzzled people for thousands of years. But in 1952, physical chemist Willard Libby, a professor at the University of Chicago in Illinois, finally provided a concrete answer to one of the site’s most enduring questions: when it was built. To do this, Libby used a brand-new geochemical technique that he had been developing based on the radioactive isotope carbon-14. Only a few years later, his work on this groundbreaking technique earned him a Nobel Prize for Chemistry.

The Washington Monument's Apex

Mon, 26 Oct 2015 12:11:30 -0400

An aluminum pinnacle has graced the Washington Monument since 1884, but subsequent modifications have changed the look of the point. In 1885, after the first major lightning strike to the monument, engineers were alarmed to find that the electricity had cracked a stone beneath the aluminum pyramid. They quickly outfitted the monument apex with a copper band and small lightning rods connected to a series of copper rods running down the corners of the stonework and connected to the internal lightning rods. In 1934, engineers discovered that the aluminum itself had deteriorated after years of lightning strikes. They replaced the copper band with eight larger copper rods extending 15.2 centimeters above the aluminum apex, hoping to shield the point from enough electricity to preserve the stone obelisk’s peak. So far, it has.

March 23, 1821: Bauxite Discovered

Mon, 26 Oct 2015 11:47:18 -0400

When Napoleon III commissioned this aluminum baby rattle for his son, Eugene Louis Jean Joseph, aluminum was more costly than silver. Credit: courtesy of Alcoa, Inc.

Compared to gold, silver, lead and copper — metals that people have extracted, refined and used for millennia — aluminum is a relative newcomer. Pure aluminum was more valuable than gold when it was first discovered in the early 19th century. It graced the fine china of Napoleon III and was displayed next to the French Crown Jewels at the 1855 Paris Exhibition. Today, aluminum is cheap and plentiful, used in everyday products ranging from soda cans to jets. The transformation of the metal from unknown material to rare metal to ubiquity in fewer than two centuries is due to two pivotal discoveries: an abundant aluminum ore — bauxite — and a process of refining this ore using electricity.

Benchmarks: January 13, 1404: England prohibits Alchemy

Mon, 26 Oct 2015 10:12:18 -0400

Many philosophers, scientists and clerics were also alchemists, including Sir Isaac Newton and English astrologer and mathematician John Dee (right). Credit: ©iStockphoto.com/HultonArchive.

Alchemy, in both ancient and medieval times, wasn’t just about turning lead into gold, although such “transmutation” was certainly one desirable goal. In a broader sense, alchemists were both philosophers and the precursors to modern chemists, in that they sought to understand the different states of matter, the interactions of metals, and the way in which elements were created from the original chaos. There were thought to be four elements — earth, air, fire and water — and combining them properly could produce any substance on Earth, from medicines to gold. Among the more lofty ambitions of alchemists was the search for the fabled Philosopher’s Stone, a substance that was supposed to enable the transmutation of one substance into another (and perhaps act as an elixir of life).

Marine microorganisms drive summer clouds over Southern Ocean

Fri, 23 Oct 2015 11:43:18 -0400

Organic material lofted into the atmosphere with sea spray is a major source of cloud condensation nuclei over the Southern Ocean, particularly in the summer months when phytoplankton bloom prolifically. Credit: Daniel McCoy.

The Southern Ocean surrounding Antarctica is home to some of the most pristine air anywhere on Earth. And yet it’s also one of the cloudiest places on the planet, a seeming contradiction because water droplets require particulate matter in the air to condense into clouds. Now, a study looking at cloud droplet concentrations over the Southern Ocean is giving scientists a clearer understanding of the role played by marine microorganisms in cloud formation and climate.

Fossil fuels diluting atmospheric radiocarbon

Fri, 23 Oct 2015 11:36:39 -0400

Credit: Callan Bentley.

Radioactive carbon-14, or radiocarbon, is used to date fossils and artifacts and study ecosystems, as well as to solve crimes and run medical tests. But these applications could be in jeopardy, according to new research illustrating how atmospheric radiocarbon will be diluted by fossil fuel emissions in the coming century.

Ancient lakes may have been refuges for early life

Fri, 23 Oct 2015 11:16:11 -0400

Scientists collected 1.2-billionyear- old lake sediments from this cliff at the Bay of Stoer in northwestern Scotland to measure molybdenum supply. Credit: Samuel Spinks.

All life needs nitrogen to build essential molecules like proteins, RNA and DNA. And to acquire nitrogen, cells need molybdenum. But molybdenum is thought to have been very scarce in Mesoproterozoic oceans 1.6 billion to 1 billion years ago, potentially stalling the evolution and diversification of life in this period, which was then entirely microscopic. New research, however, is revealing that lakes during this time contained relatively high levels of molybdenum, suggesting life may have continued evolving in those settings.

Geologic Column: Thanksgiving's unsung hero

Fri, 23 Oct 2015 10:57:46 -0400

Frontispiece from issue 41 of Godey's Lady's Book (1850) featuring engraving of editor Sarah Josepha Hale. Credit: Public Domain.

In America, we are approaching Thanksgiving, a time when we gather with family, friends and loved ones to celebrate and give thanks. We are also sharing a moment with our distant ancestors. Throughout human history, virtually every culture has celebrated harvest, including ancient Greeks, Romans, Hebrews, Persians, Chinese, Egyptians, Celts and Native Americans, among others. Our contemporary Thanksgiving is related in spirit to every one of those ancient festivals. But have you ever wondered how Thanksgiving came to be celebrated on the fourth Thursday of November?

Comment: Remarkable geology sets new Berryessa Snow Mountain National Monument apart

Fri, 23 Oct 2015 10:24:20 -0400

The southern end of Berryessa Snow Mountain National Monument includes Berryessa Peak. Credit: Andrew Fulks/Tuleyome, tuleyome.org.

In the Coast Ranges west of Sacramento, Calif., within easy driving distance of San Francisco, lies a wilderness of steep-sided canyons, mountainous terrain and fields of wildflowers. Bald eagles soar overhead, rock layers stand on end, and numerous unique plant species abound. Renowned for its biodiversity, this area is finally garnering deserved appreciation for its world-class geologic features too.

Flaring our way out of a water crisis

Thu, 22 Oct 2015 13:08:39 -0400

Natural gas is flared as oil is produced in North Dakota. Credit: Tim Evanson, CC BY-SA 2.0.

In the process of providing the energy we consume, oil and gas producers around the world use large quantities of clean water, generate massive amounts of wastewater, and purposefully set ablaze a portion of their natural gas production. The volume of water is tremendous, and enough energy is “flared” to power more than 50 million U.S. homes every year. In many places in the world, the freshwater needed for such operations is scarce; and natural gas flaring releases greenhouse gases and produces light pollution. Given the recent boom in oil and gas production in the U.S., it seems that these issues may not be going away anytime soon. However, with some clever engineering, we could pit these environmental liabilities — wastewater production, overuse of freshwater and gas flaring — against one another to solve all three at once.

Getting there and getting around Cyprus

Thu, 22 Oct 2015 12:00:57 -0400

In the Troödos foothills near Paphos is an eerie village that was abandoned in the late 1960s following a powerful earthquake that damaged nearly all of the buildings. Credit: both: Terri Cook and Lon Abbott.

Indigenous grapes, including the white xynisteri and the red maratheftiko varietals, are cultivated, crushed and fermented to create some delicious and relatively inexpensive Cypriot wines. Credit: Terri Cook and Lon Abbott.

Cyprus has been populated for centuries by a mix of ethnic Greeks and Turks. Periodic ethnic tensions erupted into communal violence in 1963, leading to a Turkish invasion in 1974. Turkey has controlled the northern third of the island ever since. The Troödos Mountains, which host the ophiolitic rocks, rise in the center of the island, within the Republic of Cyprus.

Northern Cyprus' "Peace Water" Pipeline

Thu, 22 Oct 2015 11:57:03 -0400

A pipeline, shown here under construction in May 2014, will bring water from Turkey to Cyprus. Credit: ©Shutterstock.com/muratart.

With its semi-arid climate and growing population, Cyprus suffers from the highest level of water stress in Europe and is ranked in the top five most water-stressed countries in the world, according to the World Resources Institute. Demand in the larger southern Republic of Cyprus is predicted to increase to 314 million cubic meters per year by 2020, up from 266 million cubic meters in 2004.

Travels in Geology: Cyprus: Island of Oceanic Crust

Thu, 22 Oct 2015 11:22:53 -0400

The soul of Cyprus lies in the Troödos Mountains — a rare, intact sliver of ancient oceanic crust — and in the beautiful mountain villages dotting their slopes. Credit: ©Shutterstock.com/Konstantin Kopachinsky.

The eastern Mediterranean island of Cyprus played a pivotal role in the development of plate tectonic theory. Thus, when planning a recent eastern Mediterranean trip, we, as geologists, deemed it almost blasphemous not to include a visit to Cyprus on our itinerary. We had to see for ourselves the rocks that were so instrumental to the development of this geological paradigm. When our research revealed that Cyprus also hosts famous archaeological sites dating from Neolithic to Roman times, Byzantine churches listed as a World Heritage site, classic Mediterranean cuisine and wine, and gorgeous beaches, the decision to visit Cyprus was an easy one.

Down to Earth With: Geophysicist Julian Lozos

Tue, 20 Oct 2015 12:57:07 -0400

Julian Lozos at a bluegrass music festival in Parkfield, Calif., a town that sits atop the San Andreas Fault. Credit: Julian Lozos.

Julian Lozos, a postdoctoral researcher affiliated with both the U.S. Geological Survey and Stanford University, designs computer models that simulate earthquakes. As a graduate student at the University of California at Riverside (UC Riverside), Lozos discovered part of what makes the San Jacinto Fault — a major fault in Southern California underlying the homes of millions — tick. For this work, Lozos received the Outstanding Student Presentation award at the annual meeting of the Seismological Society of America three years in a row, an unprecedented accomplishment.

Geomedia: Film: Banff Mountain Film Festival is geologic showcase

Tue, 20 Oct 2015 12:48:03 -0400

Poster for the Banff Mountain Film Festival short film "Delta Dawn." Credit: Pete McBride.

The Banff Mountain Film Festival World Tour is a traveling collection of outdoor adventure films that feature the stories of climbers, alpine skiers, mountain bikers and other mountaineers, which are often set against geologically astounding backdrops.

Peculiar shape of hair ice linked to fungus

Mon, 12 Oct 2015 14:46:27 -0400

Hair ice is named for its resemblance to tufts of fine silver hair. Its individual strands grow up to 10 centimeters long but are roughly just one one-hundredth of a millimeter thick. Credit: G. Preuss and C. Mätzler

If you have ever taken a morning hike through the woods and seen strange, silky-looking ice on fallen logs, you might have been observing a phenomenon that has puzzled hikers and scientists alike for at least a century. In a new study, researchers examining so-called hair ice have unraveled an explanation for these peculiar formations.

Tree of life reshaped

Thu, 08 Oct 2015 10:38:03 -0400

Researchers considered several possible scenarios depicting the relationship between eukaryotes and two groups of archaea: the TACK group and Euryarchaeota. Three variations of scenario 1 all indicate a common, but unknown, root for all three groups, with eukaryotes being a sister lineage to either or both the TACK archaea and Euryarchaeota. Scenario 2 depicts the TACK group as the root of Archaea, with the eukaryotes and Euryarchaeota as sisters. Scenario 3 — the most likely according to the new study — depicts Euryarchaeota as the root of Archaea, with the eukaryotes and the TACK archaea as sisters. Credit: K. Cantner, AGI, after Raymann et al., PNAS, 2015.

Since the 1970s, the classic “tree of life” taught in classrooms has portrayed three domains of life — Archaea, Bacteria and Eukaryota — all descending from an unknown common ancestor. But behind the scenes, this textbook picture has been shifting. Many scientists now think the tree’s deepest root lies within the bacteria; and, even more recently, some have begun suspecting that the Eukaryota — including all animals, plants, fungi, slime molds and other organisms whose cells have nuclei — are actually an offshoot from the Archaea, paring the tree from three to two domains. Now, a new study furthers that claim, and with the help of a novel technique for parsing phylogenetic data in greater detail than ever before, suggests a revised backstory for the Archaea — and, by extension, us.

Travertine buildup reflects ancient Rome's water usage

Thu, 08 Oct 2015 10:28:56 -0400

The Anio Novus aqueduct, which now lies in ruins, once supplied Rome with copious amounts of water. Credit: Duncan Keenan-Jones.

By the third century, Rome had 11 aqueducts — engineered rivers enclosed by masonry — that supplied water to more than a million people in the metropolis, as well as to the city’s many extravagant public baths and fountains. But just how much water was being sourced from distant rivers, lakes and mountain springs has long been a mystery. Now, scientists are putting some impressive numbers to ancient Rome’s water usage based on a study of travertine deposits that built up over time in the Anio Novus aqueduct as freshwater flowed through it to the city.

Finding and tracking conflict minerals in the heart of darkness

Tue, 06 Oct 2015 10:24:06 -0400

Millions of Democratic Republic of the Congo (DRC) residents have been displaced by warring militias, funded by the minerals trade. Clockwise from top left: Refugees flee a refugee camp as gunfire erupts nearby. Children mine at the Kaji gold mine in South Kivu in the DRC. As Western consumers have become more aware of conflict minerals, they are stepping up pressure on electronics producers. Credit: clockwise from top left: Julien Harneis, CC BY-SA 2.0; Sasha Lezhnev, Enough Project, CC BY-NC-ND 2.0; Jonathan Hutson, Enough Project, CC BY-NC-ND 2.0.

fugee camp in Kitchanga, North Kivu. Credit: Sasha Lezhnev, Enough Project, CC BY-NC-ND 2.0.

Deep within the eastern Democratic Republic of the Congo (DRC), in a mountainous jungle that is home to volcanoes and silverback gorillas, lies a mining region like no other. The ore pulled from the ground here helped the U.S. build the atomic bomb and supplied the Western world’s technology revolution of the 1990s and 2000s, which brought consumers devices like the mobile phone and laptop computer.

Campi Flegrei makes its own concrete caprock

Tue, 06 Oct 2015 09:53:58 -0400

Stanford University researchers have discovered natural "concrete" that forms in the Campi Flegrei volcanic complex near Naples, Italy, which explains how, in the 1980s, the caldera withstood the most rapid uplift ever recorded. Credit: Stanford University.

In the 1980s, Tiziana Vanorio was a teenager living in the Italian port city of Pozzuoli west of Naples when the Campi Flegrei volcanic complex that underlies the town and its harbor began to stir. Between 1982 and 1984, the caldera swelled more than 2 meters — the most rapid volcanic uplift ever measured anywhere. The rising seafloor shallowed Pozzuoli’s harbor so that ships could no longer enter. The uplift was followed by a magnitude-4 earthquake and thousands of microquakes that prompted the evacuation of 40,000 residents. Thereafter, the seismicity waned and the residents returned home, but geologists were left with a puzzle: How did the caldera withstand such extreme strain and deformation for so long without rupturing?

Subducted seawater the source of fluid-rich diamonds

Tue, 29 Sep 2015 16:56:28 -0400

The cloudy outer coating surrounding this gem-quality diamond core contains tiny inclusions encasing fluids trapped when the coating formed at a depth of about 200 kilometers. Credit: Anetta Banas

Subducting oceanic plates that dive hundreds of kilometers beneath Earth’s surface carry with them cargoes of sediment and seawater. As the plate heats up the deeper it sinks, this seawater not only initiates melting in the rock above it, but can also trigger diamond formation, suggest the authors of a new study in Nature.

Benchmarks: December 4, 1992: The Seattle Fault Zone is described

Mon, 28 Sep 2015 11:06:34 -0400

In 1992, researchers confirmed the existence of the Seattle Fault that runs through Seattle, Wash. They also confirmed several other faults that run beneath the city. Credit: ©iStockphoto.com/Jeremy Edwards.

Since the early 1900s, scientists, boaters and residents have known that a ghostly, submerged forest of dead trees lurked just below the surface of Lake Washington, on Seattle’s eastern edge. The trees were mostly too deep to bother anyone until the Lake Washington Ship Canal opened in 1916, connecting the lake and Puget Sound and dropping the level of the lake three meters. Then the dead trees — many of which were still upright — became hazardous to boaters. In response, the U.S. Coast and Geodetic Survey and U.S. Army Corps of Engineers blasted and chained down 186 trees in one submerged forest. Forty years later, when a diver visited a different underwater forest in 28 meters of water, he found himself in a dense grove of dead trees — predominately Douglas fir — the largest of which had a circumference of 9 meters.

Benchmarks: February 3, 1953: Jacques Cousteau's "The Silent World" is published, opening a window on the underwater world for millions

Fri, 25 Sep 2015 08:44:36 -0400

The Silent World. Credit: Captain J.Y. Cousteau with Frederic Dumas.

Few names are as evocative as Jacques Cousteau. The sunlight-infused blue glow of the marine subsurface, the endless array of otherworldly creatures that populate the ocean, and masked divers stealthily easing through the sea — trailed, of course, by glittering streams of bubbles emanating from Cousteau’s famed contraption — are morsels of the vivid imagery that his name often brings to mind. And with good reason: After all, he’s the one who introduced us to the real world below the waves, long before Bob Ballard found the Titanic or the Discovery Channel showed us what it’s like to swim with the sharks.

Benchmarks: March 1913: The first complete geologic timescale is published

Wed, 23 Sep 2015 13:14:34 -0400

Arthur Holmes circa 1912. Credit: Wikimedia Commons.

Ask a geologist when the Paleogene Period started and odds are very good the answer will be about 65.5 million years ago. Ask about the Carboniferous and you’ll likely hear 359 million years ago. Ask how old Earth is and the answer will almost invariably be 4.55 billion years, give or take a few tens of millions of years. Today, most geologic ages are well established and widely agreed upon. But the geologic timescale wasn’t always so settled.

Benchmarks: April 1916: "Jingo the Stegosaurus" campaigns to keep the U.S. out of World War I

Wed, 23 Sep 2015 12:52:00 -0400

In March 1935, a smaller model of the original Jingo was used to protest a speech in Philadelphia, Pa., by U.S. Secretary of War George Henry Dern in which he called for increased military spending. Credit: Peace Collection/Swarthmore.

David B. Williams

Ice (Re)Cap: October 2015

Mon, 21 Sep 2015 12:15:05 -0400

The hydro-fracture scarp and exposed lake bed of Greenland's North Lake following a rapid drainage event in 2011 are seen here. Credit: Ian Joughin.

Kennewick Man related to modern Native Americans

Mon, 21 Sep 2015 11:41:42 -0400

Cast and facial reconstruction of Kennewick Man. Previous morphometric analyses suggested he was related to the Ainu people of Japan, but a new genomic analysis shows he is more closely related to modern Native Americans. Credit: Chip Clark, Smithsonian.

After two decades of controversy surrounding the origins of Kennewick Man — a 9,000-year-old skeleton found on the banks of the Columbia River in Washington state — a genomic analysis has revealed that he was, in fact, related to modern Native Americans. The 1996 discovery of the well-preserved skeleton led to a protracted legal battle among scientists, Native American tribes and the federal government over the disposition of the remains, and sparked a scientific debate about the origins of the first Americans.

Ancient asteroids boiled Earth's oceans

Mon, 21 Sep 2015 11:28:06 -0400

Donald Lowe and Gary Byerly examine Archean rocks that preserve evidence of impacts in South Africa. Credit: Donald Lowe.

The asteroid that wiped out the remaining dinosaurs — save for the avian variety — 66 million years ago was roughly 10 kilometers wide. Long before that, however, early Earth was bombarded by many larger impactors, which pulverized Earth’s surface time and again. Now, a new study published in Geology suggests that two asteroids, dating to Archean times and estimated to be 50 to 100 kilometers in diameter, released enough energy to boil the oceans and reduce sea level by as much as 100 meters or more.

Source of Red Sea's mysterious cannon earthquakes revealed

Mon, 21 Sep 2015 11:16:00 -0400

Cannon-like blasts sometimes accompany small earthquakes in the Abu Dabbab region of Egypt along the coast of the Red Sea. Credit: Marc Ryckaert, CC BY 3.0.

For decades, people living along Egypt’s Red Sea coast have reported hearing loud blasts accompanying the small earthquakes that regularly jolt the Abu Dabbab region. And there is evidence the sounds have been occurring for much longer: Abu Dabbab means “the Father of Knock” in Arabic, hinting at a tectonic mystery at least as ancient as the name of the long-inhabited coastal region. Now, scientists are offering a novel explanation for the uniquely noisy seismic events, and their discovery is revealing new information about the underlying structure of the Red Sea region.

Aerosols help mitigate ill effects of Amazon fires

Mon, 21 Sep 2015 10:54:42 -0400

Taken by NASA's Aqua satellite, this image shows deforested areas and active forest fires (red dots) in the Brazilian state of Mato Grosso on Aug. 12, 2007. Credit: NASA Earth Observatory/Jesse Allen.

Forest fires across the Amazon Basin — many of which are set intentionally to clear land for human use — burn thousands of square kilometers each year, releasing roughly 240 billion kilograms of stored carbon to the atmosphere. According to a new study, however, the vast amounts of black carbon and other aerosolized particles also sent into the skies by such fires offset much of this carbon loss by stimulating increased photosynthesis.

Energy Notes: March 2014-2015

Fri, 18 Sep 2015 10:25:05 -0400

Credit: The American Geosciences Institute.

U.S. Oil & Petroleum Imports (million of barrels per day)

' Oil and petroleum imports data are preliminary numbers taken from the American Petroleum Institute’s Monthly Statistical Report. For more information visit www.api.org.

Mineral Resource of the Month: Iodine

Fri, 18 Sep 2015 10:19:58 -0400

Emily K. Schnebele, a mineral commodity specialist for the U.S. Geological Survey, compiled the following information on iodine, which is primarily used in X-ray contrast media, pharmaceuticals, disinfectants and LCD screens.

Iodine-depleted soils underlie some of the world's most populated areas, leaving many at risk of iodine deficiency. Its consequences, including goiter, are combated with salt iodization programs like this one sponsored by the U.N. World Food Program in Senegal in West Africa. Credit: WFP/Isabelle Dia.

Iodine is a bluish-black lustrous solid (violet-colored in its gaseous state) found primarily in seaweed, underground brines associated with petroleum deposits and caliche ore deposits.

Step one: Soil testing

Thu, 17 Sep 2015 10:23:56 -0400

Several gardening practices can be used to remediate soils to lower lead contamination. Credit: Center for Urban Health.

The first step in planning a community or backyard garden should always be to get the soil tested, getting a read on not only pH and nutrient levels, but possible contaminants like lead and arsenic. “Some cities have public health programs to help residents get their gardens tested for low or no cost, but it’s kind of hit or miss,” says Gabriel Filippelli, a biogeochemist at Indiana University in Indianapolis. Some cities such as Philadelphia have also held one-day “soil kitchen” workshops where people can bring in samples of soil for immediate testing with an X-ray fluorescence instrument.

Down to Earth With: Glaciologist Erin Pettit

Thu, 17 Sep 2015 10:17:25 -0400

Glaciologist Erin Pettit is an associate professor of geology and geophysics at the University of Alaska at Fairbanks. Credit: Ted Scambos.

Pettit mentors participants in the Girls on Ice program as they learn mountaineering and science skills. Credit: Girls on Ice/Erin Pettit.

If it has to do with frozen water, Erin Pettit has probably studied it. As an associate professor of geology and geophysics at the University of Alaska at Fairbanks, Pettit investigates all things ice. Her research spans vast spatial scales, from the behavior of entire glaciers down to the structure of individual ice crystals. And it has taken her from Alaska to Greenland to Antarctica, and to many of the mountain ranges in between.

Sculpting the Alps

Fri, 04 Sep 2015 11:25:06 -0400

Above about 1,800 meters, the steepness of mountain slopes in the vicinity of the Mont Blanc Massif near Chamonix, France, tends to decrease with elevation. Credit: Lucas Joel.

Mountains typically get steeper the higher you climb. The European Alps are an exception: Beginning at altitudes between about 1,500 and 2,000 meters, most slopes in the range tend to become less steep with increased elevation. This is largely caused by ancient glaciers, which scoured away much of the rock from the tops of the Alps. However, the steepness of alpine slopes also decreases in areas beyond the reach of glaciers, although the reasons why have remained elusive. New research is revealing how tectonic and fluvial forces have also helped shape the Alps’ unusual topography.

Declining U.S. water use a challenge for models

Fri, 04 Sep 2015 10:56:58 -0400

In 2013, the desert city of Tucson, Ariz., delivered the same amount of water to its customers as it did in 1989, when the population was roughly 30 percent lower, thanks in part to the increasing popularity of xeriscaping and smaller pools and lawns. Credit: sonorangardensinc.com/xeriscapes-tucson.

Americans are using less water today than they have at any time since 1970, according to a report by the U.S. Geological Survey (USGS), which has tracked water use since 1950 and issues reports every five years.

Getting there and getting around Hells Canyon

Thu, 03 Sep 2015 12:57:23 -0400

Rafting trips begin below the 100-metertall Hells Canyon Dam. Credit: Mary Caperton Morton.

The Snake River is still plentiful in smallmouth bass. Credit: Mary Caperton Morton.

The closest major airports to Hells Canyon are Missoula, Mont., Boise, Idaho, and Spokane, Wash. If you book a multiday trip with a reputable rafting company, the company will likely help you arrange shuttles to the beginning and end of the canyon, or you may need to rent a car. Most Hells Canyon river trips end in Lewiston, Idaho, which also has a small airport with regularly scheduled flights to Salt Lake City, Seattle and Boise.

Damming the salmon

Thu, 03 Sep 2015 12:53:34 -0400

Salmon used to be plentiful in the Snake River; today, wild salmon populations are less than 10 percent of their pre-European settlement numbers. Credit: Mary Caperton Morton.

In the 1940s, the state of Idaho decided that the Salmon River would be left to flow freely while the Snake would be developed for hydroelectric power to become Idaho’s workhorse river. To date, a total of 15 dams have been built along the Snake for a variety of purposes, from irrigation to flood control to hydroelectricity. Hells Canyon is home to three hydroelectric impoundments: the Brownlee, Oxbow and Hells Canyon dams, built in 1959, 1961 and 1967, respectively. Together they have a maximum capacity of 391 megawatts of power production.

Travels in Geology: Rafting the Pacific Northwest's heavenly Hells Canyon

Wed, 02 Sep 2015 15:07:19 -0400

Hells Canyon, the deepest gorge in North America, is challenging to get to, but it's great to raft or boat. Credit: Mary Caperton Morton.

Hells Canyon forms part of the Oregon-Idaho border. Credit: both: K. Cantner, AGI.

Why would you ever visit a place called Hells Canyon? Especially given how hard it is to get there: Few roads and only steep, difficult trails run down into the 2,400-meter-deep gorge — the deepest canyon in North America — which forms part of the border between Oregon and Idaho. Despite its remote and rugged challenges, however, Hells Canyon has attracted visitors for thousands of years, from the Clovis people and Native Americans to turn-of-the-century gold miners, sheep ranchers and homesteaders.

Jelly volcano reveals eruption trigger

Wed, 02 Sep 2015 12:13:58 -0400

The remnants of numerous sills of solidified magma radiate from West Spanish Peak in Colorado. New research suggests that the formation of new sills underground may play a role in triggering volcanic eruptions. Credit: Mary Caperton Morton.

What makes a volcano erupt? Over the years, scientists have proposed a litany of potential triggers, but there’s always room for one more. With help from dyed water, a laser and a tank of clear jelly, researchers have proposed a new mechanism that might push loaded volcanoes toward eruption.

Injection experiment offers new view of fluid-filled faults

Wed, 02 Sep 2015 11:52:36 -0400

Researchers deployed a new sensor to study the influence of fluid injection on a fault from a tunnel that is part of an underground research facility in southeastern France. Credit: Yves Guglielmi.

Scientists have known since the late 1960s that injecting fluids underground can cause earthquakes if those fluids find their way into slip-prone fault zones. Evidence of fluid-induced quakes has continued mounting in recent years with observations of abnormally high levels of seismicity in the central U.S., coincident with increased injections of wastewater into the ground — mostly related to oil- and gas-mining operations. But understanding the inner workings of fluid-filled faults is challenging because researchers have been limited by how close they can get to study them. Now, a new study is offering a glimpse into the future of induced-seismicity studies by monitoring fault motions on the spot and in real time.

Benchmarks: December 1, 1959: Antarctic Treaty Signed

Tue, 01 Sep 2015 11:23:01 -0400

A victory for peace and science

In 1911, Roald Amundsen was the first person to mark the South Pole. Credit: Steve nicklas/noS, nGS (noAA).

Science trumps all in Antarctica. For the past 50 years, Antarctica has remained a military-free, globally shared continent, dedicated to peace and scientific advancement, thanks to the Antarctica Treaty.

Benchmarks: October 9, 1865: First Successful U.S. Oil Pipeline

Tue, 01 Sep 2015 10:48:38 -0400

"Colonel" Edwin Drake (right) standing in front of the engine house and derrick of his well at Oil Creek, Pa., circa 1861. Credit: Drake Well Museum.

When Americans think of domestic oil, they likely think of Texas, Alaska or California — vast fields of towering derricks and quietly dipping oil pumps. The American oil industry, however, originated on the other side of the country in the forested wilderness of northwestern Pennsylvania. One of the most pivotal moments in the industry’s early history occurred in October 1865, when Samuel Van Syckel completed more than eight kilometers of underground pipe to transport oil from Pithole, Pa., directly to the railroad. From there, it would go on to Oil City, Pa., and then to major industrial centers, like Pittsburgh.

Benchmarks: September 16, 1987: Montreal Protocol Signed

Tue, 01 Sep 2015 10:26:04 -0400

Stratospheric clouds facilitate ozone depletion. The ice in these clouds provides a surface on which ozone-destroying chemical reactions occur. Credit: Photograph by Lamont Poole, NASA Langley Research Center.

Each year in late September to early October, atmospheric scientists watch with anticipation as ozone concentrations over Antarctica drop, opening a window in Earth’s defenses against harmful ultraviolet radiation. This ozone “hole” grew steadily in the 1990s and set a record for its size in 2006: At its peak, the hole covered an average area of 27 million square kilometers, approximately the size of North America. But scientists think that the overall ozone layer is on the slow road to recovery, thanks to the Montreal Protocol — one of the most successful international environmental agreements in history.

Arctic climate change marked by warmer, wetter conditions

Thu, 27 Aug 2015 15:00:14 -0400

New satellite data show that the skies over the Arctic Ocean are warming, which is increasing humidity and cloud cover over the region. Credit: NASA/Kathryn Hansen

At least since satellite observations began four decades ago, climbing temperatures have chipped away at Arctic sea ice, causing earlier spring melting and later autumn freezing. Because ice reflects more sunlight than water does, shrinking sea-ice cover means that Arctic waters soak up more solar energy, which affects climate both regionally and globally. Now, a new study has documented how Arctic warming leads to wetter air and increased cloud cover, particularly during autumn and winter, which spurs even more warming in a self-reinforcing cycle.

Hazardous Living: Maps, according to geologists

Tue, 25 Aug 2015 19:04:17 -0400

Credit: Kent Ratajeski and Callan Bentley

If you have geologist friends, you may have run across some humorous world maps on social media lately. These maps have garnered lots of attention — both positive and negative, the latter especially from those living in Kansas. Italian geologist Samuele Papeschi started the trend by making the map of “Europe according to a geologist,” as seen from a European geologist’s point of view. EARTH’s cartoonist-geologist Callan Bentley (a professor at Northern Virginia Community College) and Kent Ratajeski, a geologist at the University of Kentucky, followed up with a map of the U.S. as seen by American geologists. Bentley then created South America (according to an American geologist), and Papeschi created Antarctica and Asia (both according to a European geologist). As Bentley and Papeschi told me, these maps are intentionally vague (especially Antarctica and South America) and humorous. As far as I know, no one has done an Australian or African one yet.

Getting there and getting around the Whitsundays

Mon, 24 Aug 2015 11:26:55 -0400

Visitors to the Whitsundays often come through Cairns, which is also a gateway to the Great Barrier Reef. Credit: Terri Cook and Lon Abbott.

The gateway airports to the Whitsundays are on Hamilton Island and near Proserpine on the mainland. Neither hosts direct flights from the U.S., but both connect to Sydney and Brisbane, Australia’s primary international arrival points, as well as Cairns, the most popular access point to the Great Barrier Reef. From Proserpine, Whitsunday Transit can transport you to accommodations throughout the region.

Travels in Geology: Australia's Whitsunday Islands: Sun, sand and silicic volcanism

Mon, 24 Aug 2015 11:07:06 -0400

Whitehaven Beach on Whitsunday Island is perennially voted one of the top 10 beaches in the world. Credit: ©iStockphoto.com/Shane_Pedersen.

Whitehaven Beach is the only beach within all the Whitsunday Islands that has sand that is 99 percent pure quartz. Credit: Terri Cook and Lon Abbott.

In 2009, Tourism Queensland launched a campaign soliciting applications for what they billed as “the Best Job in the World”: “caretaker” of Australia’s Whitsunday Islands for six months. Benefits included transportation to Hamilton Island, the isles’ commercial hub, accommodation in a multimillion-dollar mansion and an extravagant salary. What responsibilities did the job entail? Mostly, it involved exploring the tropical paradise that is the Whitsunday Islands and documenting these explorations through photo diaries, blogs and web videos. Applications were only accepted by web video.

Ultraviolet lights the way for rare earth recycling

Mon, 24 Aug 2015 10:21:03 -0400

The 17 rare earth elements, widely used in everyday devices from cellphones to magnets and fluorescent lights, aren’t all that rare. They are just finely dispersed in small quantities around the world, making them difficult to mine in substantial quantities. Recycling rare earths is an attractive means to supplement freshly mined stocks, but it remains technically and logistically difficult. Now, a team has developed a more efficient method of recycling two rare earth elements — europium and yttrium — using ultraviolet (UV) light instead of traditional methods involving chemical solvents.

Sea-level rise accelerating

Fri, 21 Aug 2015 12:16:47 -0400

Sea-level rise has been accelerating around the planet, which has been more precisely measured by correcting for vertical land movement. Credit: ©Andjam79, CC BY 2.0.

Studies tracking sea-level rise over the past few decades have been all over the map, with reports variously indicating that the rate of rise has accelerated, stayed constant or declined. Now, a new GPS-based study published in Nature Climate Change indicates that sea-level rise has indeed been accelerating over the last decade.

Ocean 'sneezes' spread algae-infecting virus

Fri, 21 Aug 2015 11:56:13 -0400

A scanning electron micrograph of the common coccolithophore Emiliania huxleyi. Credit: Elena Kartvelishvily and Daniella Schatz.

Microscopic phytoplankton, or microalgae, permeate ocean surfaces, sometimes forming huge blooms visible from space. Nutrient concentrations in seawater are known to regulate such blooms, which play a major role in oceanic food chains and carbon cycling, and occasionally prove harmful to other marine life as well as humans. Less understood are the other factors that influence a bloom’s onset and demise. New research sheds light on one such influence, demonstrating that an algae-infecting virus can become airborne and travel long distances, potentially infecting and eradicating parts of a bloom hundreds of kilometers away.

Seismometers listen for falling rocks

Fri, 21 Aug 2015 11:48:06 -0400

Fresh debris lines part of Yosemite Valley after a rockfall. Credit: National Park Service.

Scores of natural rockfalls occur in California’s Yosemite Valley every year, often with little or no advance warning, posing hazards to people and infrastructure. In 1980, for example, a fall near Yosemite Falls killed three people and injured 19. Efforts to record and document rockfalls are rudimentary, relying only on eyewitness accounts and after-the-fact observations of fresh talus piles, which means many events are likely going unreported. In a new study, however, researchers interested in whether there’s a better way to monitor these events propose that seismic and infrasound sensors can help keep tabs on the granite slabs dropping from Yosemite’s cliffs.

Map shows where lightning zaps most

Fri, 21 Aug 2015 09:14:55 -0400

Credit: NASA Earth Observatory/ Joshua Stevens.

Lightning strikes far more often over land than sea and is more concentrated closer to the equator — both testaments to the greater atmospheric instability over those parts of the planet. These are just two observations evident from a global map of lightning strikes produced recently by NASA based on nearly two decades of data from the OrbView-1/Microlab satellite and the Tropical Rainfall Measuring Mission satellite. The new map color-codes Earth by the average number of lightning flashes seen annually per square kilometer — brighter colors mean more lightning — and refines earlier efforts based on fewer data. So where on Earth does lightning strike most? That would be in eastern Democratic Republic of Congo, which is struck roughly 150 times per square kilometer each year, followed by the area near Lake Maracaibo in Venezuela. If you look closely, you can also see the contributions of certain orographic features like the Himalayas and the Rockies on lightning-strike patterns.

Energy Notes: February 2014-2015

Thu, 20 Aug 2015 13:05:31 -0400

Credit: The American Geosciences Institute.

U.S. Oil & Petroleum Imports (million of barrels per day)

' Oil and petroleum imports data are preliminary numbers taken from the American Petroleum Institute’s Monthly Statistical Report. For more information visit www.api.org.

Mineral Resource of the Month: Bromine

Thu, 20 Aug 2015 13:02:28 -0400

Emily K. Schnebele, mineral commodity specialist for the U.S. Geological Survey, compiled the following information on bromine, which is primarily used in flame retardants, well drilling and water treatment.

The Phoenicians mixed secretions from Murex sea snails, which bind bromine atoms in seawater, with the plant dye indigo to form Tyrian purple, an expensive and highly prized dye that did not easily fade. The silk burial shroud of Charlemagne — the first emperor of the Holy Roman Empire, who was buried in Germany in 814 and repeatedly exhumed and reburied — remains a vibrant purple today. Credit: French National Museum of the Middle Ages.

Bromine, along with mercury, is one of only two elements that are liquid at room temperature. Bromine is a highly volatile and corrosive reddish-brown liquid that evaporates easily and converts to a metal at extreme pressures — above about 540,000 times atmospheric pressure. Bromine occurs in seawater, evaporitic (salt) lakes and underground brines associated with petroleum deposits.

Geologic Column: September 26, 1774: The man, the myth, the legend of Johnny Appleseed is born

Thu, 20 Aug 2015 12:45:54 -0400

Drawing of Jonathan Chapman, aka Johnny Appleseed from 1862. Credit: Public Domain.

You’ve probably heard about Johnny Appleseed, who, according to story and song, spread his apple seeds across America’s Midwest. But, unlike other figures from American folklore such as Paul Bunyan, Rip Van Winkle and Pecos Bill, Johnny Appleseed was a real man with a life far richer and more interesting than the legend.

Down to Earth With: Engineer Jeffrey Bielicki

Thu, 20 Aug 2015 12:02:32 -0400

Jeffrey Bielicki is an assistant professor of energy policy at Ohio State University. Credit: Ohio State University.

With degrees in mechanical engineering, business administration and public administration from a variety of prestigious universities, one might get the impression that Jeffrey Bielicki is an inveterate academic with his head buried in books. And, indeed, Bielicki has spent most of his career in research, looking into solutions for problems in engineering, energy and policy. But far from narrowing his focus, Bielicki’s schooling in multiple disciplines has given him the desire and ability to see issues from a range of perspectives, thus informing and broadening his approaches to solving them.

Volcanic lightning turns ash into glass

Fri, 07 Aug 2015 10:30:39 -0400

Within the ash plumes of explosive volcanic eruptions, collisions among countless pyroclastic particles sometimes lead to the buildup of static charges that discharge dramatically as volcanic lightning. In a new study, researchers have found that this lightning can, in turn, melt and fuse ash particles into distinctive glassy grains called spherules. Identifying and studying these spherules could help scientists better understand past and future eruptions, the study’s authors suggest.

Geomedia: Toys: LEGO® geoscientists break through the brick ceiling

Thu, 06 Aug 2015 10:50:10 -0400

Ellen Kooijman, a Dutch geochemist at the Swedish Museum of Natural History, won a LEGO Group design contest with her kits featuring female scientists — a first for the toy company — including an astronomer, a paleontologist and a chemist. Credit: Ellen Kooijman/LEGO Ideas.

Many adults probably remember the childhood fun of LEGO® toys, the plastic bricks from which you could build forts, cars, houses, planes, cities and even whole universes. The few simple shapes and colors encouraged unlimited creativity, limited only by the number of LEGO pieces you had, which could total in the thousands.

Fate of atolls not necessarily tied to sea-level rise

Thu, 06 Aug 2015 10:31:06 -0400

The island of Funagogo on the eastern side of Funafuti Atoll, Tuvalu. Credit: Paul Kench.

The western Pacific Ocean is home to many atolls: rings of low-lying islands built from calcite sands and the erosional remnants of coral reefs. This region is also home to some of the highest rates of sea-level rise in recent decades — an unsettling fact for the atolls’ inhabitants and others worried that rising waters will eat away at the islands and evict residents for good. But according to a new study documenting long-term change at one Pacific atoll, the future for such islands might not be so bleak.

Thorny plant marks West African diamond deposits

Thu, 06 Aug 2015 10:24:56 -0400

Editor’s note: This story was updated on Oct. 9, 2015, to fix an error in the size of the kimberlite pipe. West Africa is famous for diamonds, brought up from the depths of Earth’s mantle eons ago during explosive volcanic eruptions. On the surface, the eroded remains of these eruptions, known as kimberlite pipes, are infamously hard to find under the thick jungles of Guinea, Sierra Leone and Liberia, and only a few of the deep, narrow pipes contain profitable diamonds. Now, a researcher has identified an unusual feature that might point the way toward such pipes, and possibly revolutionize the search for diamond-rich deposits: a tall, thorny palm-like plant that seems to only grow atop kimberlites.

Trip-planning resources

Thu, 06 Aug 2015 10:17:30 -0400

Shannon Falls can be seen from the Sea-to-Sky Highway, along which many of the field trip stops were located. Credit: International Association for Geoscience Diversity.

If you are thinking of making one or more of your field trips accessible, the International Association for Geoscience Diversity (IAGD), an organization charged with advocating for students and geoscientists with disabilities, can help. The IAGD is establishing a consortium of accessible field courses, specifically developed to accommodate students with disabilities who are working to complete the field-based learning requirements of an undergraduate geoscience degree program. The IAGD can connect you with experienced students and faculty who can help you plan your accessible field course, design a new course or retrofit an existing one based on the diverse physical needs of your students. If you are interested in learning more about modifying or developing an accessible field course, or in promoting an accessible geoscience field course through the consortium, contact the IAGD at info@theiagd.org.

Geology for everyone: Making the field accessible

Thu, 06 Aug 2015 09:43:35 -0400

The design of this field trip at last year's Geological Society of America meeting in British Columbia created the opportunity for all participants to engage in the field activities that best suited their abilities. Credit: International Association for Geoscience Diversity.

On Oct. 18, 2014, at the annual meeting of the Geological Society of America (GSA) in Vancouver, British Columbia, the society hosted, for the first time, a field trip that was fully accessible to geoscience students and faculty with disabilities. The trip, which we led, is bringing attention to an often-ignored issue in the geosciences. Many students with sensory, physical or intellectual disabilities may be potentially discouraged from pursuing geoscience degrees when faced with course requirements that involve physically rigorous field-based learning.

Getting there and getting around Texas' Trans-Pecos

Mon, 03 Aug 2015 10:30:46 -0400

If you’re driving through West Texas on Interstate 10, which runs from Jacksonville, Fla., to Santa Monica, Calif., you’ll pass right through the Trans-Pecos region. Commercial air service is also available into El Paso International Airport, located about 170 kilometers west of Guadalupe Mountains National Park. A car is necessary to get around the area; you can rent one at the airport if you choose to fly in. Fall is a great time to visit the region, once the summer heat has waned.

Beached iceberg alters Antarctic marine communities

Mon, 20 Jul 2015 17:27:14 -0400

While the extent of sea ice in the Arctic has fallen substantially over the last several decades, the total area covered by sea ice around Antarctica has grown, with increases in some regions outweighing declines in others. This means that some parts of the Southern Ocean that were once ice-free and exposed to sunlight are being covered over, darkening the waters below and causing shifts in local ecosystems.

Bechmarks: June 1, 1873: The Modoc-Lava Beds War Ends

Mon, 20 Jul 2015 11:16:03 -0400

Expansive basalt lava beds cover much of the arid landscape, along with sagebrush and low vegetation, in Lava Beds National Monument. Credit: ©iStockphoto.com/JeffGoulden.

By Timothy Oleson

Energy Notes: January 2014-2015

Fri, 17 Jul 2015 10:01:47 -0400

Credit: The American Geosciences Institute.

U.S. Oil & Petroleum Imports (million of barrels per day)

' Oil and petroleum imports data are preliminary numbers taken from the American Petroleum Institute’s Monthly Statistical Report. For more information visit www.api.org.

Mineral Resource of the Month: Gemstones

Fri, 17 Jul 2015 09:58:34 -0400

U.S. Geological Survey mineral commodity specialist Donald W. Olson has compiled the following information on gemstones, which are prized above other minerals for their beauty, rarity and worth.

Red beryl, also known as scarlet or red emerald, is one of the rarest gemstones in the world, selling for as much as 0,000 per carat. Credit: ©Rob Lavinsky, iRocks.com – CC-BY-SA-3.0.

Gemstones have been treasured objects throughout history, often serving as symbols of power and status for rulers and the wealthy. Stones used in early jewelry-making include amber, amethyst, coral, diamond, emerald, garnet, jade, jasper, lapis lazuli, pearl, rock crystal, ruby, serpentine and turquoise.

Ice (Re) Cap: August 2015

Fri, 17 Jul 2015 09:47:48 -0400

An eerie red ooze, rich in microbes and iron oxides (hence the color), issues from Blood Falls at the toe of Antarctica's Taylor Glacier. Credit: National Science Foundation/Peter Rejcek.

Early Earth enriched by iron rain

Fri, 17 Jul 2015 09:35:31 -0400

The Z machine in Albuquerque is roughly 30 meters across and is used to generate electric currents of up to 20 million amps. Credit: Randy Montoya.

Iron is one of the most common elements in the Earth’s mantle and core, most of it having come from massive collisions with asteroids and other would-be planets as the early solar system took shape. But why our planet’s rocky mantle contains so much of the metal, which theory suggests should have sunk to the core, has left researchers stumped. Now, with the help of the world’s largest radiation source, scientists have replicated the conditions of early planetary formation to take a closer look at how Earth’s iron-rich mantle — and the moon’s conversely iron-poor mantle — came to be.

Southbound icebergs off the hook for ice-age cooling

Fri, 17 Jul 2015 09:27:00 -0400

A new study suggests that southbound icebergs probably arrived too late to be the trigger for Pleistocene cooling events in the North Atlantic. Credit: ©kaet44, CC BY 2.0.

During the Late Pleistocene, changes in North Atlantic Ocean circulation triggered abrupt changes in global climate: In some locations in the Northern Hemisphere, average temperatures dropped by as much as 10 degrees Celsius within a few decades. Scientists have long thought that freshwater from melting icebergs traveling south from the Arctic may have instigated the circulation shifts that contributed to cooling feedback loops. But now, scientists looking at seafloor sediments collected near Iceland have found that pulses of icebergs typically arrived after the onset of cooling episodes, too late to be primary drivers of climate change.

Stalled slabs sometimes stopped by mineral strengthening

Thu, 16 Jul 2015 13:23:14 -0400

In some subduction zones, the downgoing slabs get stuck at depths of about 1,000 kilometers, held up by some unseen barrier that might be related to high-pressure-induced strengthening of minerals in the rocks surrounding the subducting slabs. Credit: K. Cantner, AGI.

Subduction of tectonic plates into the mantle functions as an eons-long recycling system for Earth’s crust and lithosphere. But in some subduction zones, the downgoing slabs seem to get stuck at depths of about 1,000 kilometers, held up by some unseen barrier on their journey deeper into the lower mantle. Now, scientists propose that this barrier might be related to high-pressure-induced strengthening of minerals in the rocks surrounding subducting slabs at these depths.

Bark beetles not to blame for big fires?

Thu, 16 Jul 2015 13:19:11 -0400

Bark beetles flourish in warm, dry conditions and have killed millions of hectares of pine forests in the western U.S. Credit: Don Becker, USGS.

Since the mid-1990s, outbreaks of voracious bark beetles have devastated more than 71,000 square kilometers of forests in the Rocky Mountain West. Contrary to popular belief, however, the huge swaths of standing dead trees left behind don’t necessarily pose an increased fire hazard, according to a new study. The finding calls into question the efficacy of recently enacted policies entailing the thinning of beetle-killed forests.

Nonnative plants not a problem in Britain

Thu, 16 Jul 2015 12:14:04 -0400

Japanese knotweed has been classified as a destructive invasive species in several countries, including the U.K. and the U.S. Credit: ©MdE, CC BY-SA 3.0 de.

In many places in the world, nonnative plants are epidemic, outcompeting local flora for space and resources and sometimes leading to extinctions of native plants. But a new study finds that, in Britain at least, foreign plants don’t seem to be negatively impacting the natives after all.

As an aerosolizer, dust devils demoted

Mon, 13 Jul 2015 11:41:05 -0400

Dust devils look fierce, but don't lift much dust into the atmosphere, according to new research. Credit: ©Noel Feans, CC BY-2.0.

Dust is an inescapable byproduct of a rocky planet reworked by tectonic forces, extraterrestrial impacts and human activities. And though it may seem like a nuisance, airborne dust plays an integral role in the Earth system, fertilizing downwind ecosystems and influencing climate. But just how dust gets lofted into the air has long puzzled scientists. Previous studies have suggested that dust devils could stir up as much as a third of the atmosphere’s dust budget, but new work reveals these twisters contribute just a tenth of that amount.

Widening the window of human dispersal into Arabia

Mon, 13 Jul 2015 11:13:12 -0400

In a quarry near the city of Al Ain, in the eastern part of the emirate of Abu Dhabi, scientists found evidence of recurring wet climates in the Arabian Peninsula dating back roughly 160,000 years. Credit: ©Nepenthes, CC BY-SA 3.0.

The vast sea of sand that is much of the Arabian Peninsula presents a formidable barrier to travel, even with today’s modern conveniences. How and when our ancestors crossed this dry expanse after leaving Africa — on their way to populating the rest of the world — has long been a mystery. Now, a new paleoclimate study paints a wetter picture of Arabia during the time of human expansion, and the findings may change scientists’ thinking about the route and timing of early human migrations out of Africa.

Brachiopod die-off signaled mid-Permian mass extinction

Mon, 13 Jul 2015 10:35:33 -0400

The Kapp Starostin Formation on Norway's Spitsbergen Island holds clues to a mass extinction event roughly 262 million years ago in the Middle Permian. Credit: Dierk Blomeier

Since the explosion of complex lifeforms before the turn of the Cambrian, the expansion of life on Earth has been punctuated by a quintet of global mass extinctions known as the “Big Five.” The biggest of these happened toward the end of the Permian Period about 252 million years ago, when 95 percent of all species went extinct. In a new study, scientists have proposed that a sixth global extinction, about 10 million years before the End-Permian die-off, should be added to the list.

Geologic Column: Field Sketches

Mon, 13 Jul 2015 10:30:49 -0400

Field sketch from a page of, 'The Geology of New Hampshire: a report comprising the results of explorations ordered by the legislature.' Credit: Public Domain.

I’m not into camping, climbing or caving, but I like fieldwork. My mom, a science teacher, introduced me to collecting minerals and fossils. Before my senior year of high school, I followed my best friend to a 6-week summer research program at the University of Florida. When asked to choose a subject, I listed geology almost by default and was paired with a grad student studying groundwater seepage into a lake. Thirty-five years later, I’m still doing the same kind of work. I enjoy the relevance and intellectual challenge: It’s like playing MacGyver, trying to solve a puzzle with missing pieces and a limited set of tools. And the aesthetic appeal of being outdoors reinforces my occasional sense of accomplishment.

Aquifers contaminated by Supertyphoon Haiyan storm surge

Wed, 08 Jul 2015 14:52:02 -0400

University of Texas at Austin geoscientst Philip Bennett tests water wells in the village of San Antonio on Samar Island, Philippines, two months after Supertyphoon Haiyan made landfall in November 2013. Credit: Bayani Cardenas

Supertyphoon Haiyan, which battered the Philippines in November 2013, was the most powerful hurricane to make landfall ever recorded. One recent study suggested behemoths like Haiyan, which had maximum sustained winds of about 310 kilometers per hour, might warrant the creation of a new hurricane classification, “Category 6.” In addition to the thousands of deaths and casualties, flattened homes and widespread debris, Haiyan left other, less visible signs of damage in its wake, including to the fragile coastal aquifers that many residents rely on as their sole source of drinking water. Now, a new study has quantified damage done to these environmental resources, and how long it might take for them to recover.

Benchmarks: August 3, 1958: USS Nautilus crosses the North Pole

Tue, 07 Jul 2015 11:59:01 -0400

The USS Nautilus entering New York Harbor in May 1956, two years before its famous voyage to the North Pole. Credit: Library of Congress.

Cmdr. William Anderson (seated) and navigator Lt. Shep Jenks (standing) confer aboard the USS Nautilus during its transpolar voyage in 1958. Credit: U.S. Navy.

As the USS Nautilus glided through the black depths of the Arctic Ocean, Cmdr. William Anderson asked the crew for quiet. A tense silence hung over the dull roar of the propellers and the sharp pings of sonar as the submarine closed in on its destination. “Eight … six … four,” Williams counted down over the intercom, accelerating as they got closer, “three … two … one …”

Geomedia: Books: Iceland's eruption of biblical proportions explored in 'Island on Fire'

Tue, 07 Jul 2015 11:23:46 -0400

"Island on Fire: The Extraordinary Story of a Forgotten Volcano That Changed the World," by Alexandra Witze and Jeff Kanipe, Pegasus, 2015, ISBN: 978-1605986746.

For a few months in 2014–2015, a volcanic eruption in Iceland captivated many people around the world. The Holuhraun lava field produced the largest volume of lava erupted on the North Atlantic island in the past 200 years. Except for the areas plagued with acrid, sulfur-rich gas, which affected air quality, the eruption was mostly harmless and became a tourist spectacle. It was Icelandic volcanism at its finest.

Travels in Geology: Touring Texas' Trans-Pecos

Mon, 06 Jul 2015 13:46:38 -0400

The Trans-Pecos region, part of the Chihuahuan Desert, bears little resemblance to eastern Texas, which is flatter, wetter and more populated. Credit: ©Adbar, CC BY-SA 3.0.

When Robert T. Hill first arrived in Texas in 1874 at the age of 16, little was known about the geology of the arid, far-western corner of the state. While working at his brother’s newspaper in the frontier town of Comanche, Hill, who would come to be known as the Father of Texas Geology, became fascinated by fossils along the slopes of the region’s blocky buttes. After searching for information on the rocks he was looking at, Hill realized they’d never been formally described. With his enthusiasm growing, he returned to the eastern U.S. to pursue a geology degree at Cornell University. In the course of pursuing his thesis, Hill participated in an expedition to west-central Texas, during which he defined the “Trans-Pecos” area, the remote region of the state west of the Pecos River.

The Arctic is open for research

Mon, 06 Jul 2015 13:28:27 -0400

Scientific cooperation is important in the Arctic. Here, the U.S. Coast Guard Cutter Healy meets with the Canadian Coast Guard Ship Louis S. St-Laurent. Credit: Patrick Kelley, U.S. Coast Guard.

“Science knows no boundaries, and the issues that the Arctic region faces require high-quality, trans-disciplinary and problem-based research, something which cannot be accomplished solely at the national level.” So stated Annu Jylhä-Pyykönen, Finland’s Head of Delegation to the Arctic Council’s Task Force for Enhancing Scientific Cooperation (SCTF) in an interview published on the Arctic Council’s website in March 2015.

Endangered Icebreakers: The future of Arctic research, exploration and rescue at risk

Tue, 30 Jun 2015 09:11:02 -0400

Sailing the waters of the Arctic or Antarctic requires icebreakers — ships built to withstand polar conditions and break through sea ice. Credit: U.S. Coast Guard photo by Petty Officer Prentice Danner.

The sun doesn't set in the Arctic summer. Credit: Piper Lewis.

The shipboard radar of the U.S. Coast Guard Cutter Healy shows a confused mass of yellow, the radar reflections of thousands of birds. Credit: Piper Lewis.

I had never seen so many birds in my life. The sunset turns the world a deep pink as auklets and murres spiral up to their nests on the Diomede Islands, two rocky outposts in the Bering Strait equidistant from the shores of Alaska and Siberia. The seabird observers count as quickly as they can; the shipboard radar of the U.S. Coast Guard Cutter Healy shows a confused mass of yellow at our location — the radar reflections of thousands of birds. Meanwhile, scientists in a lab on the Healy take samples of water collected at different depths below us from a rosette of Niskin bottles, while others on the aft deck collect plankton with giant ring nets. This is life aboard a research icebreaker in the Arctic.

Racing to the future of automotive efficiency and performance

Fri, 26 Jun 2015 11:07:30 -0400

The 24-hour Le Mans race is part of the World Endurance Championship (WEC) race series, in which prototypes of the next generation of cars test the limits of speed, endurance and safety. Credit: ©Adrian Hoskins, CC BY 2.0.

“High-performance” and “environmentally friendly” are two phrases not commonly used together to describe race cars. But at the World Endurance Championship (WEC), it’s par for the course. These prototypes are the next generation of cars, testing the limits of speed, endurance and safety. And in just a few years, they may be coming to a lot near you.

Deforestation hangs climate out to dry

Tue, 16 Jun 2015 13:46:00 -0400

Between 1975 and 2001, the Rondônia region of Brazil lost 15,000 square kilometers of tropical rainforest. Credit: NASA/Goddard Space Flight Center.

Across the tropics, vast swaths of forest have been cleared to make room for crops and livestock. Beyond releasing vast stores of carbon trapped in soil and biomass, tropical deforestation has the potential to alter hydrological cycles in ways that could affect temperature and precipitation patterns around the planet, according to a new report in Nature Climate Change.

Wind whips canyons into shape

Tue, 16 Jun 2015 13:39:02 -0400

Wind may dramatically reshape canyons, both on Earth and on Mars. Credit: Noah J. Finnegan.

As a force of nature, wind is usually afforded less respect than water. Sure, it can topple trees and, in extreme cases, peel roofs off houses. But it can’t carve mighty canyons like water can — or can it? A new study suggests that geologists may have underestimated wind’s role in shaping valleys in arid environments, both on Earth and on Mars.

Did crustal chemistry buoy Western Plains?

Tue, 16 Jun 2015 13:36:35 -0400

The mighty mountains of the American West may captivate artists and adventurers with their rugged allure, but it’s the humble High Plains that intrigue certain geologists. For decades, scientists have puzzled over the origins of this vast plateau, which stretches for more than 500 kilometers east of the Rockies.

Laser experiments illuminate landslide physics

Tue, 16 Jun 2015 13:26:45 -0400

Researchers used beads filled with laser-activated dye to reveal the behavior of granular materials during landslides. Credit: Felice Frankel and Joshua Dijksman.

How does cereal pour from the box? Why do grains of wheat become wedged inside a hopper? What happens to soil when a slope collapses in a landslide? And, more broadly, what do these diverse phenomena have to do with each other?

Soil may supply surging streams after earthquakes

Tue, 16 Jun 2015 13:17:32 -0400

Earthquakes don’t just rattle buildings and psyches — they shake up the hydrological cycle too. Scientists have long noticed spikes in streamflow following big quakes, but they have yet to pinpoint the causes of these surges. While most proposed explanations conjure different ways of uncorking groundwater reservoirs, a new study suggests that at least some of this extra water may actually get shaken out of the soil.

Great drying led to great dying down under

Tue, 16 Jun 2015 13:07:22 -0400

If not for the megafaunal extinctions that wiped out many large animals at the end of the Pleistocene, the world might be a very different place today — with humans coexisting alongside still-living saber-toothed tigers, woolly mammoths and 3-meter-tall birds. The agents of these mass extinctions have been debated for decades: Were shifting climates, or our spear-wielding ancestors mainly responsible? A new study of the receding shorelines of Australia’s largest lake has found that a substantial drying of the environment, more so than human pressure, is mostly to blame for the loss of megafauna down under.

Introducing Earth's inner inner core

Tue, 16 Jun 2015 11:50:11 -0400

A humongous hunk of iron — that’s how scientists have long thought of Earth’s solid inner core. But new research suggests there’s more to it than that: namely, that the inner part of the inner core may have different physical properties than the outer part. In addition to revealing a new feature in Earth’s layer-cake internal structure, the discovery may shed light on the planet’s formation, say the authors of the study, published in Nature Geoscience.

Sediment load shapes rivers

Tue, 16 Jun 2015 11:43:57 -0400

Meanders of the Rio Beni in Bolivia. Credit: Landsat/U.S. Geological Survey.

The amount of sediment carried in meandering rivers influences how quickly the bends in those rivers migrate back and forth, according to recent research in Nature Geoscience addressing a longstanding question regarding river evolution. Meanders form when flowing water erodes one riverbank while simultaneously depositing sediment on the opposite bank, gradually creating more and more pronounced U-shaped bends. Sometimes, the rivers cut new channels across the narrow necks of such bends, isolating the abandoned meanders to form distinctive oxbow lakes.

Hydrogen chloride on the rise in Northern Hemisphere skies

Mon, 08 Jun 2015 12:44:20 -0400

Concentrations of hydrochloric acid measured over the South Pole on Aug. 13, 2004 (warm colors indicate higher concentrations). Credit: NASA/Goddard Space Flight Center.

Levels of the atmospheric pollutant hydrogen chloride have increased substantially in the lower stratosphere over the Northern Hemisphere since 2007, according to a new study. The increase, however, is not due to an influx of chlorine, but rather to a side effect of the recent slowing of stratospheric circulation that was first reported in 2005.

Comment: The arrival of the energy future

Mon, 08 Jun 2015 11:46:38 -0400

In 2014, the world added more wind-power production than coal-power production. Credit: Stan Shebs, CC BY-SA 3.0.

Transformations of resources into products and movements of products through the economic system require energy. Throughout the 20th century, energy was abundant and cheap in the developed world, at least if the accompanying cost of environmental impacts is ignored. The primary sources of energy driving our society are and have been fossil fuels. In 2013, petroleum, natural gas and coal accounted for 82 percent of U.S. energy use. Burning these fossil fuels emitted 5.39 billion metric tons of carbon into an atmosphere that today contains more carbon dioxide than at any time in the last 800,000 years. Still, signs are all around us that our energy consumption habits may be becoming more benign to the environment.

Down to Earth With: Geophysicist Peter Molnar

Mon, 08 Jun 2015 10:46:25 -0400

Peter Molnar is a professor in the Geological Sciences Department at the University of Colorado at Boulder and a fellow of the Cooperative Institute for Research in Environmental Sciences. Credit: David Oonk/CIRES.

As a graduate student in geophysics at Columbia University in the late 1960s, Peter Molnar — who had studied physics as an undergraduate — decided to sit in on a geology course for a term. When the professor began discussing cratons one day, Molnar raised his hand and asked what a craton was. Molnar still remembers the strange look he received, as if the professor were wondering, “Who let this guy in?”

Getting there and getting around the Catskill Mountain Front

Mon, 08 Jun 2015 10:30:00 -0400

We began our journey near fabled Woodstock, N.Y., which is best known for the 1969 outdoor concert that did not actually occur there. Woodstock, the music festival, was held some 100 kilometers away in the village of Bethel. Nonetheless, Woodstock is an interesting town to visit, with a vibrant arts community, and is a good spot to begin your trek. Driving is the easiest way to get to Woodstock from New York City or Albany. The Overlook Mountain trailhead is just a few kilometers from the center of Woodstock.

Travels in Geology: Hiking the Catskill Mountain Front

Mon, 08 Jun 2015 09:57:00 -0400

Credit: both: K. Cantner, AGI.

The dramatic easternmost edge of upstate New York’s Catskill Mountains goes by several names. The Algonquin called it the Wall of Manitou — Manitou being the “Great Spirit.” Geologists frequently call it the Catskill Front. Perhaps the most descriptive term for it is the Catskill Escarpment, as the range rises abruptly, and steeply, from the floor of the Hudson River Valley below.

Geoheritage: Preserving Earth's legacy

Mon, 08 Jun 2015 08:52:12 -0400

A few years ago, we toured southern China’s world-class karst topography. Steering our rusty, gearless bikes along the bumpy, dirt road required our full attention, but the views made it hard to focus. Surrounding us were dozens of sheer, gray limestone towers rising dramatically above a lush, emerald-green plain covered in rice paddies. China’s Guangxi Province is famous for this gorgeous karst scenery, the result of long-term chemical weathering of a thick stack of limestone. The character and appearance of this land, as well as its distinguishing features — towers, peaks, gorges, caves, sinkholes, springs and disappearing streams — govern which flora and fauna thrive here, and are integral to the social fabric and daily lives of the region’s people.

Tools of the trade

Mon, 08 Jun 2015 08:24:47 -0400

Computer technology is just one of the tools used by science illustrators, including Lynette Cook, whose conception of the dust and gas disk surrounding the star Beta Pictoris is shown here. Credit: NASA/FUSE/Lynette Cook.

Until a few decades ago, illustrators most often plied their trade with pencil and paper, ink, watercolors, or maybe airbrushed paints. While some still work in these media, most now rely heavily on computers, at least for the finished product. Some artists, like New Jersey-based illustrator Frank Ippolito, made the switch early on. “The promise was already there, so I was one of those early adopters who jumped in with both feet,” he says. For others, going digital became a necessity when clients started changing their expectations, says Lynette Cook, who previously worked as an artist and photographer at the Morrison Planetarium at the California Academy of Sciences in San Francisco.

Studies re-examine how major copper deposits form

Sun, 07 Jun 2015 15:23:08 -0400

The Bingham copper mine in Utah, one of the largest in the world, exploits a massive porphyry copper deposit. Credit: NASA.

Every year, the world consumes about 20 million tons of copper primarily for construction materials like electrical wiring and water pipes. Most nonrecycled supplies come from porphyry copper deposits (PCDs), which form when hot, metal-bearing fluids percolate up through Earth’s crust. But while geologists have long recognized — and exploited — PCDs, two new studies suggest they may need to rethink how these deposits form.

Science Illustrators: Making the invisible visible

Sun, 07 Jun 2015 14:12:35 -0400

Science illustrator Carl Buell's 2012 drawing brought the oldest common ancestor of all placental mammals to life, even though no fossil record of it has been discovered. Credit: courtesy of Carl Buell via AAAS.

Perched on a ledge overlooking a lush forested valley, a creature stands on a pile of leaves, craning its neck to pluck a plump insect off a nearby branch. It looks like a rodent, maybe a sleek-looking rat or a miniature possum. It has a soft white belly and a swooping fur tail that darkens at the tip. Its ears are small, delicate and oddly reminiscent of our own, and it has exactly seven teeth on its lower jaw behind its incisor. What it does not have is a name.

Ice (Re) Cap: June 2015

Mon, 01 Jun 2015 10:18:21 -0400

Researchers deploy a hydrophone in Icy Bay, Alaska, to monitor noise levels in the glacial fjord. Credit: Jeffrey Nystuen.

Colonial mining left its mark in Andean ice cores

Mon, 01 Jun 2015 09:56:18 -0400

When Spanish Conquistadors arrived in the Andes Mountains of Peru and Bolivia, they found a landscape rich in silver. Now, scientists have found evidence of Europe’s voracious demand for the metal hidden in tropical ice cores, which contain a record of colonial mining pollution stretching back to the 1600s.

Monkeys in the New World earlier than thought

Mon, 01 Jun 2015 09:36:47 -0400

A strong resemblance between a newly discovered Peruvian primate and African species supports the theory of dispersal from Africa to South America. Credit: Ron Blakey.

Monkeys originated in Africa, but how and when they first appeared in Central and South America has long been something of a mystery. Now, a new set of fossilized teeth places monkeys in South America about 10 million years earlier than previously thought.

Getting to the bottom of a tectonic plate

Mon, 01 Jun 2015 09:28:13 -0400

New Zealand provides an ideal location for imaging the base of the Pacific Plate as it dives under the southern tip of the country's North Island, which lies on the Australian Plate. Credit: K. Cantner, AGI, after C.A. Rychert, Nature, 2015.

Earth’s rigid, brittle lithosphere is broken into seven major plates, as well as many minor plates, which ride along atop a ductile layer of the upper mantle called the asthenosphere. For all we know about Earth’s cracked outer shell, however, a clear picture of the lithosphere-asthenosphere boundary at the bottom of the plates has proved elusive. Now, new research using explosives to image the oceanic plate dipping beneath New Zealand’s North Island is helping to blast away some of the uncertainty about this boundary by giving scientists a sharper look at a piece of the planet’s tectonic underbelly.

Counting 'tree' rings in fish skulls provides climate clues

Fri, 29 May 2015 12:56:07 -0400

Most fish have little structures in their skulls that record growth patterns — periods of feast and famine — just like tree rings. Now, scientists are using these structures, called otoliths, to show how fish size may decrease as a result of a changing ocean.

California's big trees dying of thirst

Thu, 28 May 2015 13:24:12 -0400

Since the early 20th century, the abundance of big trees has declined in forests across California, including in the Sierra Nevada. Credit: Jodie Wilson, CC BY 2.0

From the days of John Muir’s treks through the sylvan valleys and granite peaks of the Sierra Nevada, California’s majestic forests have attracted nature lovers from around the world. Since Muir’s death in 1914, though, dramatic changes have taken hold. Across the state’s forests, small trees are more common while large trees have declined in number, and oaks seem to be taking over where pines once ruled. A new study cites drought due to warming as a major driving force behind these changes.

Geomedia: On the web: Personalizing drought data with digital tools

Tue, 26 May 2015 13:14:19 -0400

California's current drought has been one of the worst since record-keeping began. Credit: Megan Sever.

With drought, people feel the heat while it’s happening, but understanding how current droughts fit into past trends — and what they mean for the future — is harder to grasp. Several online tools are available to help the public and decision-makers make sense of drought data. Viewers can see current and historical droughts superimposed on maps, focusing in on specific locations or broadening the view to larger regional, national or global droughts.

Megafloods mostly shaped Icelandic canyon landscape

Fri, 22 May 2015 11:54:45 -0400

In the 1920s, geologist J Harlen Bretz proposed that cataclysmic glacial megafloods had dramatically transformed the landscape of the northwestern U.S., leaving behind distinctive landforms like the channeled scablands in eastern Washington. Though Bretz’s notion, initially controversial, has long since been accepted, resolving how much landscapes are shaped by extreme events as opposed to the slow action of everyday erosion has nonetheless remained difficult.

Giant bolide hit South Africa 2.5 billion years ago

Thu, 14 May 2015 12:05:43 -0400

Tiny spherules, like those seen in this rock found in Western Australia, form when vaporized rock from a meteorite impact condenses into small, round particles. Credit: Oberlin College photo/Bruce M. Simonson.

Some of the oldest scraps of continental crust on Earth cling to the southern tip of Africa and the western edge of Australia. In both places, geologists have found rock layers rich in tiny particles called spherules. Scientists think spherules form when meteorites strike the planet, vaporizing surface rocks that then condense into small droplets, blanketing the surrounding landscape. Now, research published in Geology confirms the extraterrestrial origin of a 2.5-billion-year-old layer of spherules in South Africa, which scientists say was produced by a bolide at least as large as the one that doomed the dinosaurs.

Did volcanism drive Earth into global glaciation?

Thu, 14 May 2015 11:52:20 -0400

Basalts like the Franklin Large Igneous Province, which blanketed much of modern Canada and Siberia during the break-up of Rodinia, may have plunged the Earth into global glaciation. Credit: Galen Halverson.

Between about 720 million and 635 million years ago, Earth suffered two big chills. During these “Snowball Earth” episodes, geologists think the world’s oceans froze over and glaciers spilled from tropical coastlines. Scientists have previously suggested that intense volcanism, unleashed by the disintegration of the supercontinent Rodinia, plunged Earth into these global glaciations. New research now lends support to this so-called fire-and-ice hypothesis.

Iraq's biggest dam on unsure footing

Thu, 14 May 2015 11:42:37 -0400

Mosul Dam (left of center) impounds a large reservoir on the Tigris River and provides much of Iraq's power and water. Credit: ©Ali Haidar Khan, CC BY-SA 3.0.

The main spillway at Mosul Dam. Credit: U.S. Army photo by Staff Sgt. Brendan Stephens.

Much of Iraq’s national power grid, as well as its irrigation and municipal water supplies, depend on Mosul Dam, a large earthen structure on the Tigris River about 70 kilometers upstream from Mosul, Iraq’s third-largest city. However, the dam, constructed in the 1980s, was built upon a geologically weak foundation, raising worries about its safety.

Earth's most abundant mineral finally gets a name

Tue, 12 May 2015 13:55:52 -0400

The most abundant mineral on Earth, bridgmanite, has been named after Percy W. Bridgman, recipient of the 1946 Nobel Prize in Physics. Credit: Public domain.

Bridgmanite, earth's most abundant mineral. Credit: Chi Ma.

An elusive, high-density form of magnesium iron silicate, long known colloquially as “silicate perovskite,” now officially bears the name “bridgmanite,” after the father of high-pressure experiments, Nobel laureate Percy W. Bridgman.

Pre-settlement erosion rates illuminated

Tue, 12 May 2015 10:05:26 -0400

Researchers quantified background landscape erosion rates in the southeastern U.S. prior to European settlement by studying sediments along 10 major rivers, including the Dan River. Credit: ©MarmadukePercy, CC BY-SA 3.0.

Humans are one of the most powerful erosive agents on Earth, moving copious amounts of sediment to and fro, mainly through agriculture and development. But quantifying how much we actually move — often a necessary step for developing sustainable land management practices — hinges on determining erosion rates in an area before humans intervened. A new study using surface exposure dating to estimate pre-colonial erosion rates in the southeastern U.S. has now clarified the natural background rate in more detail than ever before, revealing the dramatic human impact on the regional landscape.

Energy Notes: November 2013-2014

Fri, 08 May 2015 12:47:52 -0400

Credit: The American Geosciences Institute..

U.S. Oil & Petroleum Imports (million of barrels per day)

Oil and petroleum imports data are preliminary numbers taken from the American Petroleum Institute’s Monthly Statistical Report. For more information visit www.api.org.

Mineral Resource of the Month: Iron oxide pigments

Fri, 08 May 2015 12:41:09 -0400

Arnold O. Tanner, a mineral commodity specialist for the U.S. Geological Survey, compiled the following information on iron oxide pigments.

Prior to the 2011 royal wedding, the roads and walkways around Buckingham Palace in London were resurfaced with stone mastic asphalt dyed red with a synthetic iron oxide pigment. Credit: ©Misterweiss.

Iron oxide pigments, natural or synthetic, are inorganic materials commonly used as coloring agents. They are valued for their resistance to color-change (especially from exposure to sunlight), chemical resistance, stability under ambient environmental conditions, nontoxicity and relatively low cost.

Benchmarks: June 1,1840: Setting out for the Copper Country

Fri, 08 May 2015 11:51:50 -0400

Douglass Houghton's survey of the geology of Michigan's Upper Peninsula led to the nation's first major mining boom. Credit: Painting by Alva Bradish, University of Michigan Archives.

On the morning of June 1, 1840, Michigan’s first state geologist, Douglass Houghton, stepped onto a small barge about to set sail on Lake Superior. The step marked the beginning of the first geological survey of the Keweenaw Peninsula — the northernmost portion of Michigan’s Upper Peninsula, which juts out into the center of the lake. Houghton and his crew would spend the summer exploring Michigan’s Upper Peninsula and recording the region’s geologic resources, including rich copper deposits known only locally at the time. That would change, however, after Houghton’s team detailed its findings in an 1841 report that spurred the nation’s first major mining boom.

Down to Earth With: Marine Geophysicist Maya Tolstoy

Fri, 08 May 2015 11:38:09 -0400

Marine geophysicist Maya Tolstoy is an associate professor at Columbia University's Lamont-Doherty Earth Observatory. Credit: LDEO.

Growing up in Scotland, Maya Tolstoy was drawn to the theater, and even briefly considered majoring in the subject in college. Instead, she chose to follow another lifelong passion and became a marine geophysicist.

Geologic Column: On the Summer Solstice

Thu, 07 May 2015 15:22:03 -0400

There is no world organization that designates the official days on which seasons begin. In fact, there are different ideas about how to define the seasons. When I was a child, summer began, for my friends and me, at 3 p.m. on the last day of school. Meteorologists and climatologists may tell you that summer begins on June 1. Astronomers, however, use the summer solstice — which falls this year on Sunday, June 21 — to mark the beginning of summer in the Northern Hemisphere and the beginning of winter in the Southern Hemisphere.

Travels in Geology: Glaciers and grapes in South Australia

Thu, 07 May 2015 10:58:17 -0400

Hallett Cove Conservation Park near Adelaide, Australia, exhibits evidence of a Permian glaciation that occurred when Australia lay at 70 degrees south latitude. Credit: Terri Cook and Lon Abbott.

Without an architecturally stunning opera house, an expansive colorful reef or an iconic redrock outcrop to boast, Adelaide is not usually considered one of Australia’s top travel destinations. But because we love Earth history as well as wine, this town on the southern coast was at the top of our Australian travel itinerary when we found ourselves on sabbatical near Sydney last year. Adelaide is a cosmopolitan city of manageable size, replete with stunning beaches and an especially accessible yet rugged corner of the Outback nearby. Best of all, visitors can observe the handiwork of successive glaciations — which covered the region between 700 million and 280 million years ago — while en route from one cellar door to the next as they tour a world-class South Australian wine region in the picturesque hills just minutes from the city.

And best picture goes to...'Dante's Peak'

Tue, 05 May 2015 09:14:12 -0400

In the 1997 movie "Dante's Peak," one of the more accurate portrayals of geologists at work, Pierce Brosnan plays USGS volcanologist Harry Dalton. Credit: ©Universal Studios via Movie Stills Database.

Our favorite cult geologist movie is “Dante’s Peak,” released in 1997. It is a good representation of the last few decades of disaster movies, and it is arguably the best and most realistic geologist movie to date.

Rock stars: Geologists on the silver screen

Mon, 04 May 2015 13:24:32 -0400

Credit: K. Cantner, AGI.

When geologists gather for a beer after work or around a campfire after a long day in the field, the conversation sometimes turns to how our profession is portrayed on film. Are geologists heroes or villains? Do they appear only in supporting roles — their parts limited to entering an office, uttering “Drill here,” and promptly leaving the scene — or are they main characters?

Shrinking snowpack projected in western U.S. as rain-snow boundary climbs higher

Fri, 24 Apr 2015 11:43:50 -0400

By mid-century, many parts of the Colorado Rockies, and elsewhere across the western U.S., once dominated by snow will see precipitation falling mostly as rain, according to recent research. Credit: T. H. Painter, Snow Optics Laboratory, JPL/Caltech

Gauging the impacts of climate change on future precipitation is challenging, especially in the western U.S., a region with highly variable temperatures, precipitation patterns and terrain. But understanding such impacts in the West — and, in particular, how much precipitation will fall as snow versus rain in the future — is important given the region’s dependence on wintertime snowfall as a freshwater resource. Now, a new study forecasts a broad shift from snow to rain for much of the West — a projection that will require attention from land and water resource managers planning for the future.

Ancient moss reveals tsunami timing

Mon, 20 Apr 2015 11:54:15 -0400

The moss found in the tsunami deposit, called Hylocomium splendens, sprouts a new growth segment in the spring that grows until autumn. Credit: Knut Rydgren.

Fishermen trawling Norway’s waters have long known of a place where the seafloor drops precipitously into the abyss. It’s called Storegga — or “great edge” — and it’s actually the steep headwall of the largest undersea landslide in recent geologic history. The slide triggered a tsunami that flooded the shores of the North Sea, reaching as far as Greenland, and likely affecting the Stone Age people that inhabited Northern Europe at the time.

More warming may mean more lightning

Mon, 20 Apr 2015 11:49:40 -0400

The continental U.S. will see more lightning in the future as storm energy and precipitation rates rise with global warming, according to new research. Credit: ©Lyoha123, CC BY-SA 3.0.

Add more lightning to the list of predicted effects of climate change. A recent study in Science forecasts a significant increase in the number of lightning strikes within the continental United States over the next century.

Yosemite's cliffs in retreat

Mon, 20 Apr 2015 10:38:20 -0400

This past winter, two athletes grabbed the world’s attention as they climbed up the sheer walls of Yosemite National Park’s El Capitan. But some geologists are more concerned with what falls down these precipitous faces — namely, rocks. Park geologist Greg Stock has developed a history of rockfalls in Yosemite valley dating back 15,000 years, which reveals how its cliffs have crumbled since glaciers disappeared at the end of the last ice age.

Could U.S. phosphate deposits help meet growing rare earth demand?

Mon, 20 Apr 2015 10:17:00 -0400

Phosphorite rocks in a number of U.S. localities were found to contain high levels of valuable rare earth elements. Credit: Ryan Shell, GFDL.

The modern world runs on rare earth metals — they are essential ingredients in light bulbs, smartphones, wind turbines and military weapons, among other uses. Currently, China supplies more than 95 percent of the global demand for rare earth elements (REEs), giving it a virtual monopoly. But new research suggests that the United States may contain vast domestic reserves of its own that could dwarf known deposits.

Geologic Column: The Rumpelstiltskin Factor

Thu, 16 Apr 2015 13:14:42 -0400

Credit: Public Domain.

The title above may sound like one of those Robert Ludlum novels that works better as a movie than it does in the author’s long-winded prose. But my intention is to emphasize the importance of names, an importance children often first learn about from fairy tales or folklore. In one of the “Children’s and Household Tales” collected by the Brothers Grimm in 19th-century Germany, Rumpelstiltskin is a dwarf whose magical abilities spring from his secret name. For the price of her first-born child, he helps a girl fool a king into thinking that she can spin straw into gold and thereby solve His Majesty’s major cash-flow problem. Rumpelstiltskin does the spinning and the grateful king makes the girl his queen. Demanding his reward, the dwarf reappears when the queen gives birth. She pleads for mercy; the dwarf relents and gives her three days to guess his name before she loses the child. If he had had a common name like Jim or Fred or even Gunter, the task would have been hard enough, but his name is an outlier among monikers. Yet, by subterfuge she discovers the answer in time, and the dwarf storms off, madder than Yosemite Sam after his cigar explodes.

Comment: When scientists come under legal attack

Thu, 16 Apr 2015 12:59:04 -0400

A fundamental tenet of science is that the search for knowledge is objective. Unfortunately, this principle has been turned on its head in recent years by politically motivated groups when scientific findings endanger their ideologies or business interests. To distract from and discredit such findings, these groups have launched legal challenges and other attacks against a small but growing number of scientists, who must then legally defend their work, correspondence and public statements.

Geoscience on Film: A parting ode to an awe-inspiring land

Thu, 09 Apr 2015 15:22:09 -0400

The colorful Indian city of Varanasi is considered sacred in Hindu religion and culture. Locals and pilgrims alike visit the famed ghats, or steps, along the banks of the Ganges in the city to partake of the river's revered waters. Credit: Diane LaMacchia

Some coral reefs bounce back after bleaching

Wed, 08 Apr 2015 15:34:56 -0400

This recovering coral reef in the Seychelles is dominated by structurally complex Acropora and Porites corals, which provide shelter for fish and other organisms. Credit: Nicholas Graham

Ocean temperatures that rise too much or for too long can harm coral reefs, sometimes causing mass die-offs that leave reefs nearly barren of live corals. But scientists don’t know if or under what conditions reefs — which provide habitat for a wide array of marine species, as well as food for millions of people around the world — can recover from such catastrophes, in part because of a lack of long-term studies tracking damaged reefs. Now, a new study suggests that, given time and the right conditions, even once-decimated reefs can recoup their losses.

Bird genomes untangle branches of avian family tree

Tue, 07 Apr 2015 13:24:30 -0400

Birds are one of the most diverse groups of vertebrates on Earth, with more than 10,000 known species. Credit: ©Shutterstock.com/Tom Reichner.

Birds, the only surviving descendants of dinosaurs, have one of the most fascinating — and perplexing — family trees in the animal kingdom. To sort it out, an international collaboration known as the Avian Phylogenomics Project has sequenced the genomes of dozens of different bird species, representing all the orders in the bird family. Even with a glut of new data, however, many questions remain about the branches of the avian family tree.

Geoscience on Film: Of tides and tigers in the world's largest river delta

Tue, 07 Apr 2015 13:00:36 -0400

Doug Prose lays low at the prow of a small rowboat as he and his group navigate the dense mangrove forest of the Indian Sundarbans. Credit: Diane LaMacchia

Geomedia: Books: Breaking New Ground

Tue, 07 Apr 2015 11:28:29 -0400

"Breaking New Ground: A Personal History," by Lester R. Brown, W. W. Norton & Co., 2013, ISBN 978-0393240061.

Agricultural scientist Lester Brown ponders the global future of agriculture, but his roots as a tomato farmer make him keenly aware of the local challenges of feeding a growing population. A 1986 recipient of a MacArthur Fellowship for his pioneering interdisciplinary work in the field of sustainable development, and the founder of the Worldwatch Institute, Brown reflects on his life and career in his autobiography, “Breaking New Ground: A Personal History.”

Getting there and getting around Nepal

Fri, 03 Apr 2015 13:26:25 -0400

A street vendor in Kathmandu selling colorful powders used in Hindu festivals, such as Diwali. Credit: Jesse Davenport.

A Nepali woman cleaning and sorting rice. Credit: Jesse Davenport.

Flights: The only international airport in Nepal is Tribhuvan International Airport in Kathmandu. There are a handful of other airports throughout Nepal, but these are much smaller and offer only domestic flights. There are a few direct flights from the U.S., but these are quite expensive. Most itineraries require at least one stop, for example, in the Middle East, such as in Qatar or Abu Dhabi, or in China or Thailand. Many flight options also offer layovers in India, although Indian itineraries require a transit visa that must be procured before traveling.

Of temperature and tone: Has climate shaped human languages?

Fri, 03 Apr 2015 13:16:43 -0400

The global distribution of tonal (blue dots) versus nontonal (orange dots) modern languages as identified in a new study. Credit: K. Cantner, AGI, after Everett et al., PNAS, 2015.

Humans today speak more than 6,500 languages, and thousands more dialects once spoken have gone extinct. Understanding how and why so many languages have evolved over human history has long been the work of linguists. Recently, however, the emerging field of geo-phonetics has begun looking into how geography — and perhaps climate — affects language. In a new study, researchers suggest that humidity and temperature, which can impact our ability to craft certain sounds, appear to have influenced the evolution of tonality in languages in different parts of the world.

Travels in Geology: A trek through Himalayan geology in Nepal

Fri, 03 Apr 2015 12:41:43 -0400

Near the Annapurna Base Camp in Nepal. Credit: Julia Rosen.

[Editor’s Note: On April 25, 2015, a magnitude-7.8 earthquake struck 80 kilometers northwest of Kathmandu, Nepal, killing and injuring thousands and devastating many of the areas written about earlier in this Travels in Geology feature. The disaster prompted the U.S. State Department to issue a Nepal Travel Alert that will remain in effect until Aug. 1, 2015.]

Geoscience on Film: Traversing the contours and culture of an ancient delta

Wed, 01 Apr 2015 10:13:26 -0400

Geoscience on Film: Setting the scene amid extreme tectonic and sedimentary processes

Thu, 26 Mar 2015 09:38:35 -0400

Aizawl, capital of the northeast Indian state of Mizoram, lines a steep ridgetop in the northern part of the tectonically active Burma Arc. Credit: courtesy of Doug Prose

Doug Prose, formerly a geologist with the U.S. Geological Survey, and his wife, Diane LaMacchia, have produced documentaries showcasing Earth and the geosciences through their nonprofit Earth Images Foundation since 1992. Recent films have included “Earth: The Inside Story” and “Italy’s Mystery Mountains," both released in 2014 and aired on PBS. Currently at work on their next project, Prose is blogging for EARTH about the filmmaking process, as well as the work of the scientists they’re covering, while on location in India. Read other posts in this series here.

Peak's appeal - and hazard - endures today

Mon, 09 Mar 2015 12:47:16 -0400

Skiing the headwall at Tuckerman Ravine, a steep-sided glacial cirque on the east side of Mount Washington in the White Mountain National Forest, has been a New Hampshire tradition since the late 1800s. Credit: ©Msheppard, CC BY-SA 3.0.

Despite the bad weather, or perhaps because of it, more than 250,000 visitors flock to Mount Washington each year. It has been a popular tourist destination since the 1850s, when hotels first sprung up on the summit (with their roofs chained to the ground). Some also claim the footpath to the top — the Crawford Path — is the oldest hiking trail in the country.

Benchmarks: April 12, 1934: Record winds buffet Mount Washington

Mon, 09 Mar 2015 12:40:22 -0400

On a clear day, views from the Mount Washington Observatory extend to the Atlantic Ocean. Credit: Mount Washington Observatory.

When Jeff Masters was 5 years old, a brutish gust of wind knocked him flat. The incident transpired on top of New Hampshire’s Mount Washington, a place that has long fascinated Masters — now a meteorologist and the founder of the popular forecasting site Weather Underground.

Ice (Re) Cap: April 2015

Mon, 09 Mar 2015 12:17:20 -0400

From Antarctica to the Arctic; from polar caps, permafrost and glaciers to ocean-rafted sea ice; and from burly bears to cold-loving microbes, fascinating science is found in every nook and crevasse of Earth’s cryosphere, and new findings are announced often. Here are a few of the latest updates.

Rome's hidden water trade led to glory, maybe ruin

Mon, 09 Mar 2015 12:07:12 -0400

Crumbling aqueducts crisscross the lands that once belonged to Rome, relics of a water system that sustained an empire. But now, research suggests that much of the water that flowed into Roman cities did not come gurgling down a conduit — it came in copious quantities of grain, imported to feed a growing population.

One-two punch of past warming may hold lessons

Mon, 09 Mar 2015 11:27:03 -0400

Cores of ancient soils collected from Wyoming's Bighorn Basin reveal new features of ancient climate change. Credit: Scott Wing, Smithsonian Institution.

Geologists are fond of the saying, “The past is key to the future.” Unfortunately, the past has been a poor guide when it comes to understanding modern climate change. Now, however, a new study suggests that one episode — a spike in global temperatures that occurred about 55 million years ago — may be a better analog than previously thought, and could yield insights into the planet’s future.

Methane be dammed!

Mon, 09 Mar 2015 11:08:51 -0400

Ponds and wetlands created by beaver dams, like this one in Rhode Island, may produce significant amounts of methane. Credit: Mary Caperton Morton.

Beavers were nearly killed off in the 19th century as trappers hunted them for their soft pelts. A successful conservation effort over the past 100 years brought the dam-builders back from the brink, but a new study published in the journal AMBIO has found that all those beaver-built ponds may be producing significant amounts of methane, a greenhouse gas.

Getting there and getting around the Andean Volcanoes

Fri, 06 Mar 2015 11:51:03 -0500

The innkeeper at the base of the mountain shows the skiers how the 2011 eruption of Volcán Puyehue reshaped the local landscape, making the map obsolete. Credit: Karin Kirk.

Loading the horses for the trip to base camp. Credit: Karin Kirk.

The towns of Puerto Montt, Temuco and Osorno make suitable jumping-off points for the region, and all are accessed via a short (and scenic!) flight on LAN Airlines south from Santiago, Chile. The volcano ski season lasts from early September through mid-October.

Andean ski volcanoes

Fri, 06 Mar 2015 11:47:11 -0500

The caldera of Volcán Puyehue is an amazing experience, but it’s not for the uninitiated. Several other Andean volcanoes offer brilliant skiing and genuine adventure in a more straightforward setting. Here are three popular options in the region.

Did a geographic shift trigger the Cambrian Explosion?

Fri, 06 Mar 2015 11:17:27 -0500

The location of the continents at the beginning of the Cambrian Period has long been difficult to resolve. Whereas one model based on paleomagnetism, for example, suggested that the oceanic separation between Laurentia and Gondwana was already fairly wide by that time (left), a new study based on geologic data proposes that the opening between the landmasses (red arrows) only initiated shortly before the Cambrian Explosion 530 million years ago (right). Credit: Kathleen Cantner, AGI.

Roughly 530 million years ago, Earth’s living cast of characters ballooned as a surge of evolutionary development led to the sudden appearance of almost all modern animal groups. Fossils from this period document the change in species, but the geologic, atmospheric and/or biotic factors that may have caused the radiation remain mysterious. Now, a new study suggests that massive changes in the positions of the continents may have played a significant role in sparking the Cambrian Explosion.

Geologic Column: Nature for couch potatoes

Fri, 06 Mar 2015 11:11:39 -0500

Walt Disney singlehandedly popularized the myth of the mass suicide of lemmings as a standard metaphor for the irrational behavior of crowds. ©russavia, CC BY-NC-SA 2.0.

Long ago, the first step in my doctoral project was to map a Precambrian metamorphic complex in Ontario’s Haliburton Highlands. As a recent immigrant to the country, I was unprepared for the immensity of the forest, and after an exhausting day navigating the Highlands “bush” the old-fashioned way (by pace and compass — GPS was 40 years away), I dreamt that night of a labyrinth of tree trunks with no way out. Years later, I came across Aldous Huxley’s “Wordsworth in the Tropics,” and it re-awoke the panic I’d felt on that early foray. There is something about great forests, wrote Huxley, “which is foreign, appalling, fundamentally and utterly inimical to intruding man … alien to the human spirit and hostile to it.” Is this notion of frightening forests some kind of Darwinian hangover from our early days on the open African savanna?

Geomedia: Books: Rediscovering the science behind Thoreau's 'Walden'

Tue, 03 Mar 2015 12:26:19 -0500

"Walden's Shore: Henry David Thoreau and Nineteenth-Century Science," by Robert M. Thorson, Harvard University Press, 2014, ISBN 9780674724785.

Last summer, I had the opportunity to enjoy a personal tour around the world’s most famous kettle pond, Walden Pond in Concord, Mass., led by geologist Robert Thorson, who recently authored the book “Walden’s Shore: Henry David Thoreau and Nineteenth-Century Science." The rainy, gray day did not diminish our hike or Thorson’s delight in sharing what he had learned from his research into Henry David Thoreau’s lifelong fascination with Walden Pond and the science behind his iconic book, “Walden.”

Can dam releases restore river ecosystems?

Tue, 03 Mar 2015 09:09:58 -0500

r flow experiments conducted on the Colorado River between 1996 and 2012 tested whether artificial floods released from the Glen Canyon Dam could restore downstream ecosystems. Credit: Anne Phillips, USGS.

Worldwide, dams store about 6,200 cubic kilometers of water — roughly three times the combined volume of water flowing in all of the world’s rivers at any given time. Currently, there are more than 47,000 large dams (taller than 15 meters) and at least another 800,000 smaller dams; an additional 1,600 dams are under construction. They impound an estimated 60 percent of the world’s rivers. While dams provide societal benefits, such as hydropower, water storage, flood control and economic growth, they also have many unintended consequences, such as altering the flux of water and sediment from the continents to the oceans; changing daily, seasonal and annual streamflow patterns; and fragmenting habitats and posing significant threats to freshwater biodiversity.

Travels in Geology: Skiing into the heart of an Andean Volcano

Mon, 02 Mar 2015 16:36:25 -0500

Stratovolcanoes in Southern Chile offer extreme skiing, otherworldly views and unforgettable adventure. Credit: Karin Kirk.

“OK, everybody,“our guide said. “Just calm down.” His voice had an edge to it, but the words were calming. “I know this is intense. But everyone take a deep breath. We’re OK. We’re almost there.” I obeyed, quieted my mind, and hoped that we were indeed almost there. He continued, with a return to his usual lightheartedness, “Remember, you wanted an adventure, and now you’re getting one.”

Kamikaze typhoons spared Japan from Kublai Khan

Mon, 02 Mar 2015 16:28:55 -0500

A new study suggests that a Japanese legend — which holds that "divine wind," or kamikaze, defeated Mongol invaders in the 13th century, as depicted in this 1847 painting by Kikuchi Yōsai — may have some merit. Credit: Public domain.

Like any good conqueror, Kublai Khan just wanted to expand his empire. So in the late 13th century, the grandson of Genghis Khan launched a mythic fleet to seize control of Japan. According to Japanese legend, however, the Mongol ships met with typhoons of equally mythic proportions, which quashed their repeated invasions — twice.

Thank subduction for Earth's nitrogen-rich air

Mon, 02 Feb 2015 09:47:23 -0500

The chemically oxidizing conditions in subduction zones might explain the enrichment of nitrogen (and high ratio of nitrogen to noble gases) in Earth's atmosphere compared to those on Venus and Mars, neither of which has active plate tectonics. Credit: Kathleen Cantner, AGI, after Sami Mikhail.

Plate tectonics underlies many of Earth’s distinctive features, from its ever-shifting continents to its colliding mountain ranges and continuously forming crust at mid-ocean ridges. According to a new study, the process might also explain another of our planet’s peculiarities: its nitrogen-rich atmosphere.

Lidar reveals Roman gold mines

Mon, 02 Feb 2015 09:40:52 -0500

Lidar maps of ancient gold mines in Spain's Erica River Valley (left), which show water channels and reservoirs used in mining operations, allow these structures to be located on aerial photos (right). Credit: J. Fernández Lozano et al.

The Romans’ thirst for gold was legendary, fueling mining operations that rival the scope and scale of modern mines. The Las Médulas mines, for example, near what is now León in northwest Spain, were massive, extending for many kilometers along the Erica River Valley. A new look at this region using lidar has revealed the extent of the ancient mining works, as well as the complex hydraulic systems used by the Romans in the first century B.C. to extract the gold.

Sharks collect storm data

Mon, 02 Feb 2015 09:25:30 -0500

The new face of hurricane research: Sharks tagged with sensors help researchers trace changing ocean temperatures. Credit: ©dollarphotoclub.com/FAUP.

Sharks are among the planet’s most prolific travelers, with some species swimming up to 50 kilometers a day in search of food and mates. Now, a program at the University of Miami plans to harness these top predators’ wandering ways to help study hurricanes.

Comment: Rebuilding geology faculty in Afghanistan

Fri, 30 Jan 2015 14:11:47 -0500

In December 2014, the U.S. ended combat operations in Afghanistan after 13 years. However, a residual force of nearly 10,000 troops remains in the country to continue training Afghan security forces and supporting counterterrorism operations. They will be joined by a team of geology and mining engineering professors, who will be mentoring the next generation of faculty at Kabul Polytechnic University (KPU), even as they search for new funding to keep the project going.

Mineral Resource of the Month: Silver

Fri, 30 Jan 2015 13:45:39 -0500

Florence C. Katrivanos, a mineral commodity specialist for the U.S. Geological Survey, compiled the following information on silver, an ancient metal with many modern applications.

This early-third-century-B.C. silver coin depicts Alexander III of Macedon, better known as Alexander the Great. The Macedonians also used silver medicinally, to treat battle wounds. Credit: The British Museum.

Silver, one of the eight precious or noble metals, has been used extensively throughout recorded history for various medical purposes, ornaments and utensils, and for its intrinsic value as the basis for trade and monetary systems. Silver has played a significant role in world history, financing a Greek victory over the Persians in 480 B.C., helping Spain become a world power in the 16th and 17th centuries, and helping fund the Union forces during the U.S. Civil War, to give a few examples.

March 29, 1936: Notes on Earth's Inner Core

Fri, 30 Jan 2015 13:35:48 -0500

Inge Lehmann worked for the Royal Danish Geodetic Institute from 1925 to 1952, heading the seismology department from 1928 until her retirement. Credit: The Royal Library, National Library of Denmark and University of Copenhagen University Library.

On March 29, 1936, Danish seismologist Inge Lehmann wrote a letter to a colleague in which she argued that seismic waves — specifically P-waves — recorded from distant earthquakes showed some anomalous characteristics. “If you had seen so many records from these distances as I have,” she wrote, “I am sure you would not doubt that the amplitudes are abnormally small.” Within the year, Lehmann published a study based on those unusual amplitudes, work that first proposed that Earth has a solid inner core inside its liquid outer core.

Down to Earth With: Mineralogist George W. Robinson

Fri, 30 Jan 2015 13:14:44 -0500

George Robinson has dedicated his life to finding, curating and sharing exceptional mineral specimens. Credit: John Jaszczak.

Many geologists understand the joyous feeling of coming across a beautiful rock in the field; George W. Robinson, who began collecting minerals at age 9, has had a lifetime full of such moments. After delving deeper into his early avocation as a teenager, he received his doctorate in mineralogy from Queen’s University in Kingston, Ontario, in 1979. He has worked as a high school earth science teacher, field collector, mineral dealer, museum curator and professor — all occupations that shared a common focus: a love of minerals.

A tantalizing treasure

Thu, 29 Jan 2015 14:32:50 -0500

Mesa Verde, the ancient Anasazi cliff dwellings.Credit: ©Andreas F. Borchert, CC BY-SA 3.0.

Some of Fenn's treasure includes a bracelet made of beads collected from Mesa Verde, the ancient Anasazi cliff dwellings, where this necklace was also found. Credit: National Park Service.

The contents of Forrest Fenn’s chest are not completely known, but Fenn has listed enough of the treasure to make the hunt truly tantalizing: 20 troy pounds of gold coins, gold nuggets the size of a man’s fist, pre-Columbian Incan and Mayan animal figures, a 17th-century Spanish gold-and-emerald ring, a bracelet with more than 250 rubies, diamonds and Ceylon sapphires, and two hand-carved Chinese jade masks.

On the trail of treasure in the Rocky Mountains

Thu, 29 Jan 2015 13:50:15 -0500

“Where warm waters halt… where warm waters halt… where warm waters halt.” For two summers, I’ve been exploring the Rocky Mountains with those words on my mind. Why those four words in particular? Because I believe they lead to a modern-day treasure chest.

Mineral Resource of the Month: Thallium

Wed, 28 Jan 2015 11:59:58 -0500

David E. Guberman, a mineral commodity specialist for the U.S. Geological Survey, compiled the following information about thallium, an extremely toxic metal used in a limited number of commercial applications.

Thallium, a grayish-white metal similar to tin in appearance, was discovered spectroscopically in 1861. Like lead, it is heavy yet soft, and can be cut easily with a knife. When exposed to air, thallium’s luster quickly tarnishes to a blue-gray color owing to the formation of a film of thallium oxide. Its concentration in Earth’s crust is estimated at 0.7 parts per million; mostly it is found in association with potassium minerals in clays, soils and granites, but in general it is not commercially recoverable from those sources. Manganese nodules, found on the ocean floor, also contain thallium.

Energy Notes: August 2012-2013

Wed, 28 Jan 2015 11:45:08 -0500

Credit: The American Geosciences Institute.

U.S. Oil & Petroleum Imports (million of barrels per day)

Oil and petroleum imports data are preliminary numbers taken from the American Petroleum Institute’s Monthly Statistical Report. For more information visit www.api.org.

Mineral Resource of the Month: Phosphate Rock

Wed, 28 Jan 2015 11:34:00 -0500

Stephen M. Jasinski, mineral commodity specialist for the U.S. Geological Survey, has compiled the following information on phosphate rock, the source of phosphorus, one of the three essential plant nutrients.

A phosphate mine in Utah, one of four U.S. states to produce the mineral resource. Credit: ©Jason Parker-Burlingham, Creative Commons Attribution 2.0 Generic.

As a mineral resource, “phosphate rock” is defined as unprocessed ore and processed concentrates that contain some form of apatite, a group of calcium phosphate minerals that is the primary source for phosphorus in phosphate fertilizers, which are vital to agriculture.

Energy Notes: September 2012-2013

Wed, 28 Jan 2015 11:12:50 -0500

Credit: The American Geosciences Institute.

U.S. Oil & Petroleum Imports (million of barrels per day)

Oil and petroleum imports data are preliminary numbers taken from the American Petroleum Institute’s Monthly Statistical Report. For more information visit www.api.org.

Energy Notes: October 2012-2013

Wed, 28 Jan 2015 08:18:08 -0500

Credit: The American Geosciences Institute.

U.S. Oil & Petroleum Imports (million of barrels per day)

Oil and petroleum imports data are preliminary numbers taken from the American Petroleum Institute’s Monthly Statistical Report. For more information visit www.api.org.

Mineral Resource of the Month: Talc

Wed, 28 Jan 2015 08:13:10 -0500

Talc, a mineral mined in more than 40 countries, is distributed and used worldwide. Robert Virta, talc commodity specialist, and Brad Van Gosen, talc resource specialist, for the U.S. Geological Survey, prepared the following information about the talc industry.

Mineral Resource of the Month: Wollastonite

Tue, 27 Jan 2015 12:58:34 -0500

U.S. Geological Survey Mineral Commodity Specialist Robert Virta and Resource Specialist Brad Van Gosen prepared the following information about wollastonite, an industrial mineral with sizable production only in five countries.

New York is the only U.S. state where long-term continuous mining of wollastonite has occurred. This mine in Lewis, N.Y., produces ores with up to 60 percent wollastonite. Credit: New York State Museum.

Wollastonite, a calcium metasilicate, has an ideal composition of 48.3 percent calcium oxide and 51.7 percent silicon dioxide, but it can also contain minor amounts of aluminum, iron, magnesium, manganese, potassium, sodium or strontium substituting for calcium. Wollastonite occurs as prismatic crystals that break into tabular-to-acicular fragments. It is usually white but also may be gray, cream, brown, pale green, or red depending on its impurities and grain size.

Energy Notes: December 2012-2013

Tue, 27 Jan 2015 12:50:10 -0500

Credit: The American Geosciences Institute.

U.S. Oil & Petroleum Imports (million of barrels per day)

Oil and petroleum imports data are preliminary numbers taken from the American Petroleum Institute’s Monthly Statistical Report. For more information visit www.api.org.

Mineral Resource of the Month: Selenium

Tue, 27 Jan 2015 12:44:47 -0500

U.S. Geological Survey selenium commodity specialist Micheal W. George has compiled the following information on selenium, a rare toxic metal.

Brazil nuts contain high levels of selenium. Credit: Gabriela Ramirez Galindo/Center for International Forestry Research.

Selenium, a relatively rare element with diverse uses, is widely distributed within Earth’s crust, but it does not occur in concentrations high enough to justify mining solely for its recovery. Selenium is recovered as a byproduct of nonferrous metal ore processing, principally from the anode slimes associated with electrolytic refining of copper. Slimes from primary copper refining can contain as much as 10 percent selenium, but are generally much lower.

Down to Earth With: Deanna D'Alessandro

Tue, 27 Jan 2015 10:41:46 -0500

Deanna D'Alessandro. Credit: Sam D'Agostino, SDP Photo.

Deanna D’Alessandro, a chemist at the University of Sydney in Australia, is working on a new material that may make it cheaper and easier to clean greenhouse gases from power plant emissions. D’Alessandro has developed crystals composed of metals and organic molecules that can trap molecules of greenhouse gases like carbon dioxide, and release them on cue — or even transform them into more useful compounds. Her work won her one of three L’Oreal Australia For Women in Science Fellowships given last year.

Down to Earth With: The Swindling Geologist

Tue, 27 Jan 2015 10:00:13 -0500

The Swindling Geologist traveled through the Midwest and Northeast in the early 1880s, impersonating famous geologist Clarence Dutton among others. The real Dutton is seen here. Credit: NOAA Photo Library.

When Clarence Dutton spoke, people listened. As one of the most famous geologists of the late 1800s, he regularly attracted large crowds to his talks. He also had a way with women. The president of an Indiana literary society once wrote to Dutton to confirm a lecture and assured the speaker that “the ladies would be delighted to see him again.”

Down to Earth With: Matt Kuchta

Tue, 27 Jan 2015 09:43:04 -0500

Credit: ©Matt Kuchta.

Matt Kuchta is the geology program at the University of Wisconsin at Stout (UW-Stout), located in Menomonie, Wis. It’s a young program: Kuchta is in just his second year as a tenure-track assistant professor, after working as an adjunct instructor at the undergraduate instruction-focused school for two years while pursuing a doctorate in geology from the University of Wisconsin at Madison, which he received in 2009.

Down to Earth With: Pat Pringle

Tue, 27 Jan 2015 09:24:18 -0500

Pat Pringle at Henderson Inlet, Puget Sound, where he and colleagues have sampled submerged trees. Credit: Michael Polenz, Washington State Department of Natural Resources.

After finishing a master’s degree in geology at the University of Akron in 1982, Pat Pringle left the relative flatlands of Ohio’s Allegheny Plateau and went west to pursue his passion. More specifically, he went northwest, to the U.S. Geological Survey’s (USGS) Cascades Volcano Observatory, lured by the steaming vents and layered debris flows of the recently awakened giant, Mount St. Helens. He was smitten.

Down to Earth With: Lee Allison

Tue, 27 Jan 2015 09:15:38 -0500

Lee Allison is director of the Arizona Geological Survey. Credit: Courtesy of Lee Allison.

_Editor’s Note: Lee Allison was head of the Arizona Geological Survey until his unexpected death on Aug. 16, 2016. EARTH interviewed him in 2012 and spoke with him about the latest issues in Arizona geology, especially the complicated politics of potash and uranium mining. Allison was a great friend to the geosciences and to EARTH. More info can be found here: _http://www.azgs.az.gov/news_releases2016.shtml#aug17.

Down to Earth With: Geologist Kyle House

Mon, 26 Jan 2015 13:13:36 -0500

Kyle House. Credit: Courtesy of Kyle House.

Kyle House, a research geologist for the U.S. Geological Survey’s (USGS) Geology and Geophysics Science Center in Flagstaff, Ariz., gravitated to scenery at a young age when he moved from Oklahoma to western Washington and beheld the Cascade Range for the first time. He learned that rocks and landscapes can tell fascinating stories, and he developed a passion for explaining the events that shape them. While earning degrees in the geosciences, he became attuned to the value of collaboration. Any scientist working in isolation can tell only an incomplete version of a phenomenon or event, he says.

Did three convicts survive their escape from Alcatraz? Modern modeling adds to a decades-old mystery

Wed, 14 Jan 2015 10:11:00 -0500

The former Alcatraz Federal Penitentiary on Alcatraz Island in San Francisco Bay. Credit: Jon Sullivan, public domain

Twenty-first century science is shedding new light on a 53-year-old mystery involving one of the country’s most notorious prisons: Did three convicted bank robbers survive their escape attempt from Alcatraz Island? New results, presented at the American Geophysical Union’s (AGU) annual meeting in San Francisco last December, suggest there’s a chance they did.

Down to Earth With: Glaciologist Richard Alley

Tue, 13 Jan 2015 13:05:38 -0500

If you don’t know who Richard Alley is, stop reading for a minute and search for him on YouTube. Go on, this can wait. Back? What you likely saw was Alley singing his rendition of Johnny Cash’s “Ring of Fire,” in which he explains subduction zones, or another similar song. In addition to being something of an Internet sensation for his energetic lectures and songs about geologic processes, Alley is a glaciologist who studies the effects of climate change. Alley’s work has taken him to glaciers around the world, from Greenland to the Antarctic ice sheet. He is also trying to understand how best to communicate scientific ideas to the public. So far those efforts have included singing to his undergraduate classes and filming a television series for PBS called “Earth: The Operators’ Manual.” (There’s a public-friendly book and website of the same title as well.)

Down to Earth With: Snow Hydrologist Jeff Dozier

Tue, 13 Jan 2015 10:32:44 -0500

Jeff Dozier founded the Bren School of Environmental Science and Management at the University of California at Santa Barbara. Credit: Courtesy of Jeff Dozier.

It’s mid-January. Snow hydrologist Jeff Dozier relaxes at his sister’s cabin near Lake Tahoe, his bare feet resting on a coffee table. His teenage son, who spent thJeff Dozier (middle) and friends in the Hindu Kush in the 1970s.e day competing in a ski race, lounges on the couch beside his father, listening to music. Snacking on cheese and crackers, the two look utterly content.

Down to Earth With: Geomorphologist Gregory Tucker

Tue, 13 Jan 2015 10:24:21 -0500

Gregory Tucker in the Grand Canyon. Credit: Courtesy of Gregory Tucker.

As an undergraduate anthropology student, Gregory Tucker thought math was a boring subject with abstract rules that didn’t relate to his life. Today, that “boring” subject provides the foundation for Tucker’s innovative research involving numerical modeling and unique field studies that recently earned him the European Geosciences Union’s 2012 Ralph Alger Bagnold Medal, one of the highest prizes in geomorphology.

Getting there and getting around Bermuda

Fri, 09 Jan 2015 12:50:48 -0500

Several major airlines serve Bermuda’s L.F. Wade International Airport, located on St. David’s Island about 30 minutes from Bermuda’s capital and largest city, Hamilton. Dozens of bus routes can take passengers to almost any place on the island, but getting to and from the airport — or anywhere with large suitcases — on the bus is frowned upon. Instead, take a taxi. Rental cars are not available to visitors. The alternative is scooters, but nerves of steel and good health insurance are a must for navigating the narrow, windy, high-speed roads. And although the island is small — less than two-thirds the size of Manhattan — and many places are within walking distance, few roads outside Hamilton have sidewalks or even shoulders. A handful of ferry routes can also help you reach some destinations.

Ice (Re) Cap: February 2015

Mon, 05 Jan 2015 20:05:41 -0500

Surface meltwater from the Greenland Ice Sheet pours into a moulin, emptying into a network of drainage channels at the base of the glacier. Credit: Lauren Andrews.

From Antarctica to the Arctic; from polar caps, permafrost and glaciers to ocean-rafted sea ice; and from burly bears to cold-loving microbes, fascinating science is found in every nook and crevasse of Earth’s cryosphere, and new findings are announced often. Here are a few of the latest updates.

Wealth of seafloor features emerges from new survey

Mon, 05 Jan 2015 19:54:58 -0500

A new survey of Earth’s deep ocean — 80 percent of which remains unmapped — has revealed a wealth of previously unknown features, including thousands of seamounts as well as a variety of undersea tectonic features that are either buried under too much sediment or were simply too small to be seen before. Researchers led by geophysicist David Sandwell of the Scripps Institution of Oceanography used high-resolution altimetry data from two Earth-observing satellites to produce a global marine gravity model that the team described in Science as twice as accurate as earlier incarnations.

New nationwide soil map available online

Mon, 05 Jan 2015 19:45:51 -0500

The U.S. Geological Survey (USGS) recently completed a seven-year soil-mapping project detailing the mineralogy and geochemistry of soils across the lower 48 U.S. states. Bill Cannon, an emeritus scientist at the USGS in Reston, Va., and co-author of the report, which was published in 2014, discussed the effort last October at the Geological Society of America’s annual meeting in Vancouver, B.C.

North American terranes not so exotic after all

Mon, 05 Jan 2015 13:18:34 -0500

The Wrangellia Terrane extends from Vancouver Island, seen here, to central Alaska. Credit: Keith Freeman, CC BY-SA 2.5.

The cordillera of western North America is a patchwork of various landmasses, or terranes, that assembled through collision and accretion to the Laurentian Shield, leaving a complicated tectonic history for geologists to unravel.

Mantle plume alternative explains Australian volcanism

Mon, 05 Jan 2015 13:11:35 -0500

Magma often finds its way to the surface along Earth’s crustal boundaries as tectonic plates crash together, rift apart or grind past each other. Less understood is why volcanoes sometimes emerge far away from plate boundaries. Narrow plumes of buoyant mantle rock rising from hundreds of kilometers deep have long been supposed as the source of intraplate volcanoes, but evidence for plumes is lacking in many areas. Now, in a new study, researchers have reported evidence for an alternative process, known as edge-driven convection, which appears to be driving intraplate volcanism in southeastern Australia.

Scientists complete a global inventory of lakes

Mon, 05 Jan 2015 11:31:14 -0500

Oregon's Crater Lake is one of more than 117 million newly inventoried lakes around the world. Credit: Mary Caperton Morton.

How many lakes are there in the world? Until recently, the exact number was anybody’s guess. Now, a new global inventory conducted using satellite imagery has placed the count at 117 million. The GLObal WAter BOdies database (GLOWABO) includes all lakes greater than 0.002 square kilometers, which combined, cover a surface area of 5 million square kilometers, or 3.7 percent of the Earth’s nonglaciated land area.

Icebergs were the original Florida snowbirds

Mon, 05 Jan 2015 10:14:53 -0500

As icebergs drifted south along the coast, their keels plowed across the seafloor, creating the characteristic grooves shown here in a seafloor bathymetry image from offshore of South Carolina. Credit: Jenna C. Hill.

A new study shows that between 20,000 and 10,000 years ago, icebergs drifted southward off the coasts of South Carolina and Florida.

Geologic Column: February 2: A day long celebrated for its seasonal ties

Mon, 05 Jan 2015 10:06:13 -0500

February is an odd month. It is the only month not named for a god, a number or a Roman Emperor. It is named for a Roman festival, which seems appropriate this year given that February kicks off with the Super Bowl on Feb. 1. The festival, Februa, was a revel of purification. (Super Bowl Sunday is kind of the opposite!)

Energy Notes: August 2013-2014

Mon, 05 Jan 2015 09:13:27 -0500

Credit: The American Geosciences Institute.

U.S. Oil & Petroleum Imports (million of barrels per day)

Oil and petroleum imports data are preliminary numbers taken from the American Petroleum Institute’s Monthly Statistical Report. For more information visit www.api.org.

Mineral Resource of the Month: Antimony

Mon, 05 Jan 2015 09:03:11 -0500

David Guberman, the antimony commodity specialist for the National Minerals Information Center at the U.S. Geological Survey, compiled the following information about antimony, widely used in alloys and in flame retardants.

Stibnite is a principal ore of antimony. Credit: PepperedJane.

Antimony is a lustrous silvery-white semimetal or metalloid. Archaeological and historical studies indicate that antimony and its mineral sulfides have been used by humans for at least six millennia. The alchemist Basil Valentine is sometimes credited with “discovering” the element; he described the extraction of metallic antimony from stibnite in his treatise “The Triumphal Chariot of Antimony,” published sometime between 1350 and 1600. In the early 18th century, Jöns Jakob Berzelius chose the periodic symbol for antimony (Sb) based on stibium, which is the Latin name for stibnite.

Benchmarks: February 17, 1977: Hydrothermal vents are discovered

Sun, 04 Jan 2015 20:01:17 -0500

This image, taken on Feb. 17, 1977, records the discovery of deep-sea hydrothermal vents and dozens of previously unseen species of marine life. Credit: WHOI Archives ©Woods Hole Oceanographic Institution.

In early February 1977, as scientists aboard the research vessel (R/V) Knorr made their way across the Pacific waters off the northwest coast of South America, they had reason to suspect their expedition might find the success that had eluded others. Previous missions had identified their destination — a site on the ocean surface about 330 kilometers northeast of the Galápagos Islands, below which two tectonic plates rift apart — as a promising location from which to search for their intended target. Once there, the researchers would deploy a variety of tools, including manned and unmanned submersibles, to the ocean bottom in the hopes of directly spotting hydrothermal vents.

Down to Earth With: Glaciologist Lonnie Thompson

Sun, 04 Jan 2015 19:38:59 -0500

As a child growing up in Gassaway, W.Va., Lonnie Thompson was poor. When his father died while Thompson was a senior in high school, he realized he’d need to earn a reliable paycheck as quickly as possible. As an undergraduate at Marshall University in Huntington, W.Va., he knew he wanted to study science; he started off as a physics major before settling on geology. Later, when he arrived at Ohio State University (OSU) as a graduate student in 1971, Thompson’s intent was to study coal geology, a practical choice that he believed would quickly secure him a job.

Travels in Geology: Navigating the rocks, reefs and waters of Bermuda

Sun, 04 Jan 2015 18:42:20 -0500

Much of Bermuda's coastline is rocky but the south shore hosts beautiful pink and white sand beaches. Credit: Kelly Speare.

The Bermuda Triangle is not an actual scientific phenomenon. But if a family were looking for a place to disappear to for a week or so, Bermuda is a great choice. Picturesque beaches, beautiful weather and a pleasant mix of Caribbean and British cultures make it a popular vacation destination. It’s also a place where geology and history are on display, making both relaxation and exploration easy.

Pentagon report calls for military to prepare for climate change

Tue, 30 Dec 2014 10:47:27 -0500

Credit: Public Domain.

The U.S. Department of Defense (DOD) is charged with ensuring national security against threats, both domestic and foreign. Now the Pentagon has released a report detailing its strategy against a developing foe: climate change. The 20-page “Climate Change Adaptation Roadmap” outlines actions the military can take to adapt to and mitigate the effects of climate change, both at home and internationally.

New tracers can identify fracking fluids

Tue, 30 Dec 2014 10:30:32 -0500

Hydraulic fracturing to harvest natural gas has been controversial due in large part to the potential for contamination of ground and surface waters by the pressurized fluids used to force open cracks in deep shale formations and by the so-called flowback fluids that re-emerge at the surface from fracking wells. Now, researchers have developed a geochemical method of tracing fracking fluids in the environment; it’s a tool that could be used to identify hazardous spills in the future and may lead to better use and disposal of fracking wastewater.

The amazing minerals of the Larsemann Hills

Mon, 29 Dec 2014 13:41:00 -0500

Four minerals were discovered on Stornes Peninsula in the Larsemann Hills of East Antarctica based on fieldwork there from 2003 to 2004. In part because of these minerals and other rare boron and phosphate minerals found in this pristine region, Stornes Peninsula is now protected as an Antarctic Specially Protected Area — the highest level of environmental protection in Antarctica. Below are some details about these special minerals.

Protecting the mineral treasures of Antarctica's Larsemann Hills

Mon, 29 Dec 2014 12:38:44 -0500

It was late November 2003 and not quite summer in Antarctica. As the Squirrel helicopter lifted off after delivering its last load, we set about putting up our two tents and making camp on Stornes Peninsula. The peninsula, which would serve as our home and base for fieldwork for the next two months, is part of the Larsemann Hills, a 40-square-kilometer region of rocky islands and promontories on the eastern shore of Prydz Bay, some 120 kilometers southwest of one of Australia’s Antarctic bases, Davis Station. Our only contacts with the outside world were twice-daily radio calls and an occasional helicopter flight to refurbish our larder and take out our samples. No telephone, no Internet.

Bare Earth Elements: Past and present directors dissect the future of USGS

Mon, 22 Dec 2014 17:00:37 -0500

USGS headquarters in Reston, Va. Credit: U.S. Geological Survey/photo by Don Becker

December tends to be a busy time for geoscientists — likewise for those of us who cover and write about work in the field. Part of that annual year-end hustle and bustle is due to the timing of the American Geophysical Union’s (AGU) annual fall meeting, which brings together tens of thousands of scientists, exhibitors and others (including science writers and reporters) for a week’s worth of research talks, poster presentations, press conferences, workshops and countless other events.

Down to Earth With: Bruce Benson

Fri, 19 Dec 2014 09:20:41 -0500

In a remarkable career spanning nearly 50 years, Bruce Benson has held just two jobs. In 1965, a year after earning his bachelor’s degree in geology, he founded the Benson Mineral Group, an oil and gas exploration and production company that he has owned and chaired ever since. From this foundation, Benson’s business interests have spread into salvaging, banking, mortgage servicing, cable television, geothermal power, real estate and even pizza.

Satellites - not just Santa - see holiday lights

Thu, 18 Dec 2014 17:22:02 -0500

City lights shine brighter during the holidays in the United States when compared with the rest of the year, as shown using a new analysis of daily satellite data. Credit: NASA Earth Observatory/Jesse Allen.

San Francisco — This year, when Santa makes his rounds, he won’t need Rudolph to light his way. In many U.S. cities, the intensity of nighttime lighting increases 20 to 50 percent during the holidays compared to the rest of the year, according to data presented Tuesday by NASA researchers at the annual meeting of the American Geophysical Union (AGU) in San Francisco.

Down to Earth With: Lawson Brigham

Thu, 18 Dec 2014 12:40:01 -0500

Lawson Brigham, a Distinguished Professor of Geography and Arctic Policy at the University of Alaska at Fairbanks and retired U.S. Coast Guard captain, has worn many hats in his career. He has been the deputy director and Alaska Office director of the U.S. Arctic Research Commission in Anchorage; chair of the Arctic Marine Shipping Assessment of the Arctic Council, an intergovernmental forum of the eight Arctic nations; vice chair of the Arctic Council’s working group on Protection of the Arctic Marine Environment; and a contributing author to the Arctic Climate Impact Assessment.

Hazard lingers after South Napa earthquake

Wed, 17 Dec 2014 13:36:10 -0500

A damaged building in Napa, Calif., following the magnitude-6 earthquake on Aug. 24, 2014, which struck south of the city. Credit: ©James Gunn, CC BY 2.0.

San Francisco — The magnitude-6 earthquake that shook buildings and rattled wineries in California’s Napa Valley on Aug. 24, 2014, continues to affect homes in at least one neighborhood in the city of Napa more than three months later. The quake’s epicenter was about 6 kilometers south of the city, but post-quake movement, or afterslip, along the principal fault line to the north of the epicenter is ongoing, according to a fast-track report prepared by the U.S. Geological Survey (USGS) for the Federal Emergency Management Agency. Scientists involved in producing the 51-page report — released to the public on Tuesday — discussed it at a press conference at the annual meeting of the American Geophysical Union in San Francisco.

Down to Earth With: James Balog

Wed, 17 Dec 2014 11:37:05 -0500

"Chasing Ice," a 2012 documentary about photographer James Balog (above) and his quest to document Arctic ice retreat, won many awards, including one for cinematography at the Sundance Film Festival. Credit: courtesy of James Balog.

Photographer James Balog is known for his groundbreaking environmental photography that examines intersections of humans and nature. His work has appeared in publications ranging from National Geographic and Smithsonian to Audubon and The New Yorker. He has also authored eight books, including the recently released “Ice: Portraits of Vanishing Glaciers,” and he has been honored with dozens of awards, including the Heinz Award and PhotoMedia’s Person of the Year.

Down to Earth With: James White

Wed, 17 Dec 2014 11:26:31 -0500

James White is director of the Institute of Arctic and Alpine Research at the University of Colorado in Boulder. Credit: Courtesy of James White.

James White contends that he has one claim to fame: He grew up just 50 kilometers from Dolly Parton in eastern Tennessee. His father worked as a chemist at Oak Ridge National Laboratory, an enclave of science west of Knoxville. Now a chemist himself, White actually has more claims to fame than he is willing to admit. He has co-authored more than 100 peer-reviewed scientific publications; he is the director of the University of Colorado’s Institute of Arctic and Alpine Research (INSTAAR); and he has been named an Institute for Scientific Information highly cited scientist — an honor bestowed on less than 0.5 percent of all publishing researchers. White recently spoke with EARTH contributor Terri Cook about how he nearly became an oceanographer, the importance of interdisciplinary education and research, and how Superstorm Sandy could affect the public perception of climate change.

Down to Earth With: Anna Henderson

Tue, 16 Dec 2014 12:22:28 -0500

Politicians and pundits communicate with talking points. In Washington, D.C., a catchy sound bite often trumps a filibustering speech, and a grandiose idea must usually fit into only a few sentences. In science, however, communication occurs as dense journal articles or professional textbooks that flesh out complexities in minute detail. Bridging the gap between these two diverse communication styles in order to convey scientific issues to policymakers is the job of the American Geosciences Institute’s William L. Fisher Congressional Geoscience Fellows.

Down to Earth With: Tanya Atwater

Tue, 16 Dec 2014 10:45:06 -0500

Tanya Atwater is an emeritus professor at the University of California at Santa Barbara. Credit: Courtesy of Tanya Atwater.

When Tanya Atwater began graduate school in marine geology in 1967, it was considered unlucky for women to be aboard ships. Undaunted, Atwater signed up to work on the first research cruise to take a close look at a seafloor spreading center. Voyage after voyage, she and her mentors fought for her right to work on oceanographic vessels, and it is fortunate they did. Atwater has since had a remarkable career studying plate tectonics and was instrumental in piecing together the evolution of the San Andreas Fault plate boundary.

Down to Earth With: Kirk Johnson

Tue, 16 Dec 2014 10:32:02 -0500

In 1967, at a family picnic in Casper, Wyo., 6-year-old Kirk Johnson stumbled across a fossil that looked to him like an ancient rattlesnake tail (it turned out to be a brachiopod). Not long after, while hiking in his home state of Washington, he accidentally knocked over a piece of shale, fortuitously discovering a fossil leaf. The ensuing epiphany that he had a knack for finding fossil treasures led to what he now calls his “paleo obsession.”

Benchmarks: Sept. 26, 1912: Birth of Preston Cloud, geologist who deciphered banded iron formations

Mon, 15 Dec 2014 14:24:31 -0500

Public domain.

Banded iron formations (BIFs) represent some of the earliest, and most controversial, evidence that the early Earth was devoid of oxygen. These deposits — consisting of thin layers of iron, primarily magnetite and hematite, interspersed with chert, shale and quartz — were recognized for their economic value in the mid-1800s. But it wasn’t until the late 1960s when Preston Cloud, the eminent 20th-century American geologist, focused his vast and wandering intellect on their origins that they assumed their prominent role in the revelation of early Earth history.

Down to Earth With: David Montgomery

Mon, 15 Dec 2014 13:31:56 -0500

From the length and breadth of his body of work, you might assume that David Montgomery, a geomorphologist at the University of Washington in Seattle, is approaching the end of a highly successful career. After all, among other accomplishments, he pioneered our understanding of how river channels shape landscapes, explored how glaciers and climate determine the height of the world’s highest mountain ranges, and helped elucidate how erosion has shaped human civilizations through time. He has authored or co-authored more than 140 academic papers as well as three (going on four) books, and even snagged a MacArthur “genius grant” in 2008. However, Montgomery is only a youthful 51 and shows no signs of slowing down — he even manages to find time to write songs, play guitar and sing in two Seattle-based bands, Big Dirt, a folk rock group, and High Noon, a bluesy jazz rock ensemble. Recently, EARTH’s Julia Rosen caught up with Montgomery before he headed off to Africa for another season of fieldwork.

Down to Earth With: Past American Geosciences Institute Congressional Geoscience Fellows

Mon, 15 Dec 2014 13:03:47 -0500

The American Geosciences Institute’s (AGI) William L. Fisher Congressional Geoscience Fellowship provides an opportunity each year for a geoscientist to work in Washington, D.C., as a staff member in the office of a member of Congress or congressional committee. Since the fellowship program began in 1998, many fellows have used the skills and knowledge they acquired to launch careers at federal and state agencies, nongovernmental organizations and universities. Former fellows Gabrielle Dreyfus (2008-2009), Aisha Morris (2011-2012) and David Wunsch (1998-1999) recently spoke with EARTH contributor Brittany Huhmann about their experiences and how their time as fellows shaped their understanding of the role of science in public policy. Today, Dreyfus is a policy analyst at the Department of Energy, Morris is an education and community engagement specialist at UNAVCO and Wunsch is director of the Delaware Geological Survey and state geologist.

Down to Earth With: Naomi Levin

Tue, 09 Dec 2014 13:29:16 -0500

Naomi Levin is a stable isotope geochemist. Credit: Will Kirk/Homewood Photography, Johns Hopkins University.

Stable isotope geochemist Naomi Levin, a native New Yorker, says she could easily imagine alternate career paths that would have been more in line with her urban roots. But the hands-on nature of both fieldwork and lab work lured her to geology and anthropology. And after working with a string of prominent geochemists — including Jay Quade, Thure Cerling and John Eiler — as a graduate student and post-doctoral researcher, Levin has quickly moved to the top of her field.

Down to Earth With: Eric Riggs

Tue, 09 Dec 2014 13:19:18 -0500

Eric Riggs says he often tells students the story of how he got into geoscience as a cautionary tale. That may seem ironic given his current position as assistant dean for diversity and graduate student recruitment and development in Texas A&M University’s College of Geosciences. But before returning to school to earn a doctorate in mineral physics and, eventually, settling into geoscience education research, Riggs made forays into English literature, marketing and the printing business. “Don’t do it this way!” he says with a laugh. “It worked out well for me, but it was a long, twisted path.”

Marine mammals blamed for first New World tuberculosis

Tue, 09 Dec 2014 12:01:46 -0500

Fur seals in Argentina. Credit: Ricardo Bastida.

When Europeans arrived in the Americas they introduced an array of new infectious diseases that decimated the native populations. Now, a new genetics-based study published in Nature shows that the emergence of tuberculosis in Peru seems to have predated the arrival of the Spanish — and that seals and sea lions may be to blame instead for the ancient infections.

Golden Gate ghost ships rediscovered

Tue, 09 Dec 2014 11:56:13 -0500

A new remote sensing survey of the seafloor off the coast of San Francisco revealed the 1863 wreck of the clipper ship Noonday as well as others. Credit: both: NOAA.

Just beyond San Francisco’s Golden Gate Bridge is a shipwreck graveyard where as many as 300 vessels lie in silty underwater repose. A team of NOAA researchers conducting a two-year study to identify and map the long-forgotten ships in the Gulf of the Farallones National Marine Sanctuary and the adjacent Golden Gate National Recreation Area has announced the discovery of three wrecks: the 1863 wreck of the clipper ship Noonday, the 1910 shipwreck SS Selja and an unidentified early steam tugboat wreck tagged the “mystery wreck” — all now obscured by mud and silt on the ocean floor.

Skinned oceanic plates may be origin of ophiolites

Tue, 09 Dec 2014 11:48:33 -0500

Part of an ophiolite sequence in northern Italy. Credit: ©Qfl247, CC BY SA 3.0.

Long recognized as slivers of oceanic crust incongruously emplaced on land, ophiolites are distinctive sequences of basalt, gabbro and peridotite found globally near former and current convergent zones, where oceanic tectonic plates subduct under continents. But scientists don’t have a clear idea why or how ophiolites split from downgoing plates and find their way onto land. Now, a new study suggests part of the answer may relate to weak layers of mantle that allow oceanic crust to be peeled, or “skinned,” from subducting slabs as they descend.

Textbook mantle plume theory may need revision

Tue, 09 Dec 2014 11:19:20 -0500

Every basic geology textbook has a section on mantle plumes, which have long been thought to underlie certain island chains and other volcanic hot spots, but hard evidence in support of narrow columns of magma upwelling from deep within the Earth’s mantle remains scant. Now a new study suggests that the long-held plume theory should be abandoned altogether.

Old piles of shells reveal ancient El Niño patterns

Tue, 09 Dec 2014 11:00:51 -0500

An Incan-era shell midden in Peru's Ica Valley. Credit: Matthieu Carré.

Understanding of the El Niño-Southern Oscillation (ENSO) is evolving as scientists unearth new data sources. In a study recently published in Science, scientists turned to the discarded remains of shellfish for a 10,000-year record of eastern Pacific ENSO activity, which offered glimpses into unexpected past ENSO behavior and intensity.

Oil-encased water droplets are mini-ecosystems for microbes

Tue, 09 Dec 2014 10:29:16 -0500

Oil rising from underground solidifies into asphalt over much of Pitch Lake on the Caribbean island of Trinidad. In spots, it also reaches the surface as a liquid. Credit: Rainer Meckenstock.

Dark, sludgy oil may not seem like an environment suited to life. But microbes, known to make meals of such organic stews by breaking down large hydrocarbons to extract food and energy, have been found before in petroleum reservoirs. Now, in a new study, researchers report finding diverse communities of microorganisms living inside tiny water droplets in Pitch Lake, the world’s largest natural asphalt seep located on the Caribbean island of Trinidad. The discovery may have implications for industry, scientists say, as well as for our understanding of extreme life.

Geologic Column: What geoscientists can learn from TED Talks

Mon, 08 Dec 2014 13:18:01 -0500

Credit: Wikimedia Commons/©TED.

TED talks have become an international — and Internet — phenomenon. The goal of the talks, which began as a series about the alignment of technology, entertainment and design (hence “TED”), is to “share ideas worth spreading.” The presentations are pithy, conversational, focused and entertaining; they are often inspirational and sometimes very personal. Geoscientists — whether presenting conference papers, classroom lectures or presentations for general audiences — can learn a lot from TED talks, especially from the structure and guidance applied to preparing the talks.

Down to Earth With: Ecologist Chris Field

Mon, 08 Dec 2014 11:59:07 -0500

Chris Field, founding director of the Carnegie Institution's Department of Global Ecology, has won the Max Planck Research Award and the Roger Revelle Medal. Credit: Linda A. Cicero/Stanford News.

Last summer, the American Geophysical Union honored Chris Field, founding director of the Carnegie Institution’s Department of Global Ecology, with its annual Roger Revelle Award, which recognizes “outstanding contributions in atmospheric sciences, atmosphere-ocean coupling, atmosphere-land coupling, biogeochemical cycles, climate or related aspects of the Earth system.”

Geomedia: Books: Are we causing a sixth extinction?

Mon, 08 Dec 2014 11:55:35 -0500

"The Sixth Extinction: An Unnatural History," by Elizabeth Kolbert, Henry Holt and Co., 2014, 9780805092998.

Last year, Elizabeth Kolbert released her latest excellent book. Her previous volume, “Field Notes from a Catastrophe,” set a high bar for accessible, accurate science writing about environmental issues, but in my opinion, “The Sixth Extinction” surpasses it in several regards. Readers of this magazine will appreciate its solid geologic grounding and perspective, with entire chapters devoted to the end-Ordovician and end-Cretaceous extinctions, as well as sections on the principles of evolution and Earth history. Climate change, the focus of her earlier book, looms large here too, though it is just one of the many threats to the survival of our biosphere that Kolbert covers.

Getting there and getting around France's Massif Central

Mon, 08 Dec 2014 11:44:15 -0500

Le Puy is famous for the manufacturing of fuseau lace, which is still made by hand, as well as by machine. Credit: both: Terri Cook and Lon Abbott.

Vulcania, Europe's only volcanic theme park, was the brainchild of two volcanologists who were killed in the explosive 1991 eruption of Japan's Mount Unzen the year before the park opened. Credit: Terri Cook and Lon Abbott.

Most flights to France from the U.S. land in Paris. If you are heading directly to the Massif Central, you can either take a one-hour flight from Paris to Clermont-Ferrand Auvergne Airport or take the Corail Auvergne train, a 3.5-hour trip.

Travels in Geology: Lentils, lace and lava: France's Massif Central

Mon, 08 Dec 2014 11:12:18 -0500

Canoeing offers impressive views of the limestone walls of the Tarn Gorge in Cévennes National Park in France. Credit: Terri Cook and Lon Abbott.

The Massif Central is a roughly 5,000-square-kilometer highland region in south-central France filled with volcanic necks, scenic gorges and picturesque parks and towns. Credit: Kathleen Cantner, AGI.

Paragliders soar after departing from the Puy de Dôme, the highest point in the northernmost of three chains of volcanoes in the Massif Central. Credit: Terri Cook and Lon Abbott.

Tucked between the Pyrenees and the Alps in south-central France is a little-known highland called the Massif Central. This rugged and secluded region is celebrated for its natural beauty, which is preserved in several large parks that attest to the area’s long and diverse human and geologic history. At the heart of the Massif Central is the picturesque town of Le Puy-en-Velay, known for its green lentils, handcrafted lace and potent Verveine liqueur. There, an arresting trio of volcanic necks capped with historical attractions looms above medieval houses, lace workshops and cobblestone streets where pilgrims have gathered for more than a thousand years to begin their long journey to one of Christendom’s holiest sites.

A dry and ravaged land: Investigating water resources in Afghanistan

Mon, 08 Dec 2014 10:15:48 -0500

A tale of three Afghanistans: Deserts, mountain streams and growing cities. Credit: top and middle: Thomas J. Mack, USGS; bottom: ©iStockphoto.com/MieAhmt.

Aside from the front-page issues of war and politics, one of Afghanistan’s most critical national needs is safe and reliable supplies of water. The United Nations estimates that Afghanistan’s current population of about 31 million will increase by nearly 80 percent by the year 2050 to approximately 56 million. Such an increase will raise demand on the country’s already stressed water resources. In addition, recent research suggests that global climate change could alter precipitation patterns in Afghanistan. In particular, both the amount and the timing of snowfall received at higher elevations could change, impacting the major source of water for many areas in Afghanistan.

Antibacterial clays could fight superbugs

Mon, 08 Dec 2014 09:40:45 -0500

Clays with antibacterial properties found near Crater Lake in Oregon could eventually lead to new agents in the fight against antibiotic-resistant superbugs like methicillin-resistant Staphylococcus aureus, better known as MRSA, according to a new study.

Try and try again: GeoCorps application tips

Mon, 08 Dec 2014 09:19:13 -0500

Matt Dawson, seen here during his 2007 GeoCorps internship at the Upper Missouri River Breaks National Monument in Fort Benton, Mont., is now the Geo- Corps America program coordinator at the Geological Society of America in Boulder, Colo. Credit: Matt Dawson.

The competition for GeoCorps America positions has been getting stiffer each year as the number of applicants increases. Last year, the program received more than 1,400 applications for 136 summer positions.

Into the parks: A sampling of GeoCorps projects

Mon, 08 Dec 2014 09:07:00 -0500

GeoCorps projects can take participants to a variety of stunning work locations. Left: Patrick Burns, a U.S. Forest Service GeoCorps intern, worked in the Fraser Experimental Forest in the Rocky Mountains. Middle: GeoCorps participant Chris Ciervo explores the Snake Creek Cave system in Great Basin National Park in Nevada. Right: Many GeoCorps positions involve mapping abandoned mines, such as this one in Mojave National Preserve in California. Credit: all: GSA.

Applications are now being accepted for spring and summer 2015 GeoCorps America positions. The deadline is Feb. 3 at noon (Mountain Time). Fall and winter positions will be posted on May 1, with an application deadline of noon on July 1. Applicants may apply for up to three positions (although they can only accept one) and must be a member of the Geological Society of America to apply. Below is a sampling of some GeoCorps projects.

Geocorps America: Putting geoscientists to work on federal lands

Mon, 08 Dec 2014 08:38:06 -0500

The GeoCorps America program has been putting geoscientists to work on federal lands since 1997. In fall 2014, Devils Tower National Monument hosted the thousandth GeoCorps participant, Claudia Velasco. Pictured left to right: Matt Dawson, GeoCorps program coordinator; Piper Lewis, GeoCorps participant number 1001; Velasco; Linda Tokarczyk and Mike Finn, managers of community relations for Rare Element Resources, which funded Velasco's project. Credit: GSA.

In 2009, when Erica Clites was completing her masters in paleontology at the University of California at Riverside, she didn’t know what her next career move would be. Since the economic downturn beginning the previous year, unemployment for recent graduates had been high. “I didn’t really think I was going to be able to find work in the field of paleontology,” she says. But Clites had a fallback plan, which turned out to be a springboard to the career she always wanted.

November 10, 1934: Arizona declares war against California at Parker Dam

Wed, 03 Dec 2014 14:01:44 -0500

From above, tiny green irrigation circles draw a narrow buffer along the 2,300-kilometer course of the Colorado River like the brush strokes of a zoomed-in pointillist painting. These vibrant green dots stand out against the buff and ochre hues of the desert palette, a testament to the river’s life-giving waters. Less obvious are the 6.4 billion cubic meters of water that flow, or are pumped, more than 390 kilometers from the Colorado’s gorge through tunnels and canals, up and down hills, to the agricultural and population centers of Southern California each year, and the additional 3.4 billion cubic meters that gurgle toward Phoenix and central Arizona annually.

December 27, 1888: The Geological Society of America is founded

Wed, 03 Dec 2014 13:48:26 -0500

Members of GSA at a formal banquet held during the 1940 annual meeting in Austin, Texas. Credit: Courtesy of GSA.

When the Geological Society of America (GSA) held its first organizational meeting in December 1888, there were only about 200 geologists in North America. Today, as GSA celebrates its 125th anniversary, the organization has evolved into one of the world’s largest societies devoted exclusively to geology, representing more than 25,000 members — researchers, students, teachers and industry professionals with interests spanning the geosciences — in 107 countries.

January 26, 1905: The world's largest gem-quality diamond is unearthed

Wed, 03 Dec 2014 12:18:15 -0500

Glass replicas of the nine main gems cut from the original rough Cullinan. At top left is the 530.2-carat pearshaped Cullinan I, dubbed the

Each day, thousands of visitors to the Smithsonian Institution’s National Museum of Natural History view the rare and spectacular Hope Diamond, a 45-carat blue diamond. And dozens of diamonds bigger than the Hope — with names like Excelsior, Incomparable and Jubilee — have also been retrieved, cut and polished to perfection.

April 20, 1832: Arkansas' hot springs named the First National "Park"

Wed, 03 Dec 2014 11:34:44 -0500

Published in the second volume of George William Featherstonhaugh's "Excursion Through the Slave States" in 1844, this lithograph depicts Hot Springs in the mid-1830s. Lining Hot Springs Creek are a few small cabins in the center of the image and, at right, natural formations of calcium carbonate called tufa. Credit: National Park Service, Hot Springs National Park Collection.

In March 1872, not long after William Henry Jackson’s photographs from the famed Hayden Geological Survey first introduced the U.S. populace to the rugged majesty of northwestern Wyoming, President Ulysses S. Grant designated Yellowstone as the country’s first official national park. Some 40 years earlier, however, a comparatively small plot of land in Arkansas had garnered a similar designation, albeit in different terminology, from then-President Andrew Jackson.

Ice (Re) Cap: December 2014

Tue, 04 Nov 2014 12:06:57 -0500

University of Copenhagen researcher Bo Vinther, part of a team that assembled a new climate reconstruction for Greenland based on nitrogen isotopes, prepares an ice core for inspection. Credit: Christian Morel.

From Antarctica to the Arctic; from polar caps, permafrost and glaciers to ocean-rafted sea ice; and from burly bears to cold-loving microbes, fascinating science is found in every nook and crevasse of Earth’s cryosphere, and new findings are announced often. Here are a few of the latest updates.

Rainwater penetrates into ductile crust

Tue, 04 Nov 2014 11:52:06 -0500

Researchers found that rainwater penetrates into the brittle-ductile transition zone beneath New Zealand's Southern Alps. Credit: ©Jörg Hempel, CC-BY-SA-3.0-de.

Rainwater is capable of percolating deeper into Earth’s crust than once thought possible, according to a new study. The finding could impact our understanding of mountain building, the behavior of rock deep underground and the formation of hydrothermal mineral deposits.

Snow triggers quakes on Mount Rainier

Tue, 04 Nov 2014 11:41:58 -0500

Credit: ©Shutterstock.com/Bryan Brazil.

A new study indicates that more than 150,000 low-frequency earthquakes that occurred on Mount Rainier over the past decade were caused by snowfall that triggered stick-slip sliding of glaciers.

The quakes, which were too small to be felt, occurred in winter at elevations of 3,000 meters or more and repeated at regular intervals, as often as every few minutes. These “ice quakes” were clustered in week- to month-long swarms that strongly correlated with snowfall events, reported Kate Allstadt and Stephen D. Malone of the University of Washington in the Journal of Geophysical Research – Earth Surface.

Carbon tet still offensive to ozone layer

Tue, 04 Nov 2014 11:13:38 -0500

The ozone hole (purple and blue) over Antarctica, visualized from satellite data, reached its greatest extent in 2006. Levels of ozone-depleting chemicals in the atmosphere have been declining overall in the last 10 to 15 years, although carbon tetrachloride has not dropped off as rapidly as expected. Credit: NASA.

Earth’s ultraviolet light-shielding ozone layer is recovering, according to a report released in September by the World Meteorological Organization and the United Nations Environment Programme. The findings, authored by more than 250 scientists and presented as part of the latest Scientific Assessment of Ozone Depletion (SAOD), suggest the ongoing success of the 1987 Montreal Protocol and its amendments in cutting atmospheric levels of chlorofluorocarbons (CFCs) and other ozone-depleting substances (ODS’s), which have fallen by about 10 to 15 percent overall since peaking in the late 1990s.

Oceans: Where has all the plastic gone?

Tue, 04 Nov 2014 10:59:35 -0500

A piece of polyurethane foam was colonized by tentacled terebelid worms and shelled gastropods in the South Pacific Ocean. Credit: Joan Costa/Consejo Superior de Investigaciones Científicas, Madrid, Spain.

Plastic in the ocean is a growing concern, yet no one knows for sure how much debris is out there, where it is and how it affects marine ecosystems and food chains. Andrés Cózar of the University of Cádiz in Puerto Real, Spain, and colleagues recently undertook a meta-study to estimate the abundance and distribution of plastic in the global ocean.

Ancient storms recorded in Yucatán cave

Tue, 04 Nov 2014 10:50:10 -0500

Cenote Ik Kil, near Chichen Itza on the Yucatan Peninsula in Mexico. Credit: ©WikimediaCommons/Dmadeo.

Today, one can find a plethora of records about coastal storms — everything from local news footage of wading meteorologists to the moment-to-moment wind speeds and barometric pressures of entire seasons of Atlantic hurricanes recorded in NOAA databases. Ancient storms are harder to track, unless they left a mark in the geologic record. Now, researchers have a new proxy record, one of the longest to date, to study ancient storms.

Last Scottish glacier melted during big chill?

Tue, 04 Nov 2014 10:32:43 -0500

The final vestiges of an ice cap from Scotland's last glaciation are thought to have melted in Rannoch Moor. Credit: Gordon Bromley.

Scotland’s craggy peaks, deep lochs and fjord-lined coast are hallmarks of a landscape shaped by successive glaciations, the last of which, toward the end of the Pleistocene, draped the highlands with an ice cap covering 9,500 square kilometers. Rocky moraines give scientists a clear picture of the boundaries of this glaciation, called the Loch Lomond Advance, although the timeline of its growth and eventual demise has proved difficult to pin down.

When science meets film at MIT

Tue, 04 Nov 2014 10:23:31 -0500

MIT students in the Experimental Study Group learn to shoot short educational videos, even using a green screen to include special effects. Credit: Christian Cardozo.

Across the Internet, science shows abound, such as “Crash Course,” “The Brain Scoop” and “Vsauce.” A good educational video is like watching a professional ballerina — if the dance is done well, it looks effortless. Of course, neither ballet nor film is actually easy, especially when the medium is meant to carry a message. A new class at MIT is helping students break down the steps and twirls of video and having them choreograph their own short educational films — with the goal of teaching them to better communicate, and deepen their own sense of the science, by explaining complex ideas like the Big Bang, the architecture of the Wheatstone Bridge or the chemistry of bread.

Pliocene tropical oceans were warmer after all

Tue, 04 Nov 2014 10:08:07 -0500

Credit: ©Shutterstock.com/holbox.

Scientists may have overturned the idea that Earth’s tropical oceans were the same temperature during the Early to Middle Pliocene — between about 5 million and 3 million years ago — as they are today, despite the world being a far warmer place then.

Gravity builds stone sculptures

Tue, 04 Nov 2014 10:03:17 -0500

New research suggests that the formation of sandstone arches, such as Wilson Arch just south of La Sal Junction, depends on gravity. Credit: Mary Caperton Morton.

Every visitor to Arches National Park in Utah wonders how the spectacular, seemingly improbable sandstone arches form, but although there are many hypotheses, testing different ideas in the field has proved all but impossible. Now a new modeling study suggests that while arches may seem to defy gravity, their formation actually depends on it.

Energy Notes: June 2013-2014

Mon, 03 Nov 2014 19:43:46 -0500

Credit: The American Geosciences Institute.

U.S. Oil & Petroleum Imports (million of barrels per day)

Oil and petroleum imports data are preliminary numbers taken from the American Petroleum Institute’s Monthly Statistical Report. For more information visit www.api.org.

Mineral Resource of the Month: Mica

Mon, 03 Nov 2014 19:11:53 -0500

Jason Christopher Willett, a mineral commodity specialist for the U.S. Geological Survey, compiled the following information on mica.

Sheets of muscovite and biotite mica litter the ground at the Ruggles Mine in Grafton, N.H., where mica was discovered in 1803. Credit: ©James St. John, CC BY 2.0.

The mica mineral group includes 34 phyllosilicate minerals, all with a layered, platy texture. The mineral has been known for millennia: Mica was first mined in India about 4,000 years ago, where it was used primarily in medicines. The Mayans used it for decorative effect in stucco to make their temples sparkle in the sun. Today it is used in everything from electrical products to makeup.

Down to Earth With: CEO and Geo-Data miner Nicole Barlow

Mon, 03 Nov 2014 13:00:06 -0500

Nicole Barlow runs Purple Rock, Inc., a company she created to mine for nuggets of geologic knowledge stashed in old documents that fill up store rooms, boxes and filing cabinets. Credit: Nicole Barlow.

Miners are the classic geo-entrepreneurs. Nicole Barlow is a new kind of geo-entrepreneur: She also mines — but instead of rocks, she digs into dark data. That’s all the information stored away in file cabinets, boxes and geological survey store rooms. And instead of finding gold or silver, she uncovers nuggets of information and digitizes old documents.

Getting there and getting around Scotland

Mon, 03 Nov 2014 10:19:24 -0500

The main bus terminal (above) is located right next to Edinburgh's Waverly Train Station, also a hub for car rentals. Credit: Mary Caperton Morton.

To visit Scotland, fly into Edinburgh or take a train from London. Arthur’s Seat is within walking distance of the Royal Mile and downtown Edinburgh. Scotland has a good train and bus system with routes to the Highlands, but traveling between the smaller villages is easier by private car, if you can handle driving on the left-hand side of the road. The Cairngorm Mountains are best approached from Braemar, Tomintoul, Aviemore or Kingusse, all small towns with hotels and restaurants that cater to tourists visiting the park.

Bag your first Munro

Mon, 03 Nov 2014 09:18:56 -0500

Credit: Mary Caperton Morton.

One of the founding members of the Scottish Mountaineering Club, Hugh Munro, compiled a list of all the mountains in Scotland taller than 3,000 feet (914.4 meters), which are now called Munros. At present, there are 283, although this number has changed over time due to improvements in surveying and mapping. Munro-bagging is a national pastime in Scotland; for some dedicated Scots, summiting all the Munros is a lifelong project.

Travels in Geology: The inspiring, globe-trotting rocks of Scotland

Mon, 03 Nov 2014 08:21:47 -0500

One of many small lochs, also known as a lochans, in the Cairngorm Mountains. Credit: Mary Caperton Morton.

As the birthplace of both modern geology and the sport of mountaineering, Scotland is home to some incredible, inspiring rocks. For a relatively small landmass — less than 80,000 square kilometers — England’s northern neighbor boasts incredible geologic diversity — the product of a 3-billion-year tectonic journey from the South Pole to its current position.

Link between volcanoes and drought cools geoengineering prospects

Fri, 31 Oct 2014 14:26:02 -0400

Large volcanic eruptions, such as the 1991 eruption of Mount Pinatubo, can cool Earth, but geoengineering attempts to replicate the effects may lead to regional droughts. Credit: U.S. Geological Survey, photograph by Richard P. Hoblitt.

The realization that large volcanic eruptions can trigger climatic cooling has inspired some to call for stratospheric geoengineering projects, which mimic volcanic eruptions, to combat the effects of global warming. But the approach is not without risks. And a new study looking at the effects of volcanic eruptions on monsoon cycles in China over the past 700 years elucidates one: Eruptions can also cause profound drought in some regions. The finding suggests that although artificially induced cooling may have benefits in some places, it could backfire in others.

Hundreds of methane seeps discovered along the U.S. East Coast

Fri, 31 Oct 2014 14:08:21 -0400

Methane bubbles stream from seafloor sediments off the coast of Virginia north of an area called Washington Canyon. Credit: NOAA Okeanos Explorer Program, 2013 ROV Shakedown and Field Trials in the U.S. Atlantic Canyons.

The release of methane from seafloor sediments may have a significant influence on global climate, but the ubiquity and stability of such pockets is not well understood. Now the discovery of hundreds of methane seeps on the seafloor along the U.S. East Coast suggests that such reservoirs may be more common along passive margins than previously thought. The easily accessible region may prove to be an ideal natural laboratory for studying how such seafloor methane may influence water temperatures and ultimately climate.

Crystal Ball Science: In the energy sector, follow the money in 2015

Fri, 31 Oct 2014 13:00:56 -0400

Editor’s Note: We asked our staff and some frequent contributors to write a short commentary on something that they had been thinking about in 2014. We gave everyone carte blanche. What follows is a collection of extremely varied, often very personal insights into how the planet impacted each individual.

Chess as a scientist

Fri, 31 Oct 2014 12:52:16 -0400

Credit: ©Shutterstock.com/Daniel Schweinert.

Editor’s Note: We asked our staff and some frequent contributors to write a short commentary on something that they had been thinking about in 2014. We gave everyone carte blanche. What follows is a collection of extremely varied, often very personal insights into how the planet impacted each individual.

Walking - and mentoring - on the wild side

Fri, 31 Oct 2014 11:58:59 -0400

Editor’s Note: We asked our staff and some frequent contributors to write a short commentary on something that they had been thinking about in 2014. We gave everyone carte blanche. What follows is a collection of extremely varied, often very personal insights into how the planet impacted each individual.

Family inspiration for my career(s) in transdisciplinary science

Fri, 31 Oct 2014 10:28:46 -0400

Editor’s Note: We asked our staff and some frequent contributors to write a short commentary on something that they had been thinking about in 2014. We gave everyone carte blanche. What follows is a collection of extremely varied, often very personal insights into how the planet impacted each individual.

What a wonderful world to explore

Fri, 31 Oct 2014 10:02:49 -0400

Editor’s Note: We asked our staff and some frequent contributors to write a short commentary on something that they had been thinking about in 2014. We gave everyone carte blanche. What follows is a collection of extremely varied, often very personal insights into how the planet impacted each individual.

Minor miners: A brief reflection on child labor underground

Fri, 31 Oct 2014 09:45:03 -0400

Editor’s Note: We asked our staff and some frequent contributors to write a short commentary on something that they had been thinking about in 2014. We gave everyone carte blanche. What follows is a collection of extremely varied, often very personal insights into how the planet impacted each individual.

Mountains beyond mountains

Thu, 30 Oct 2014 13:44:00 -0400

Editor’s Note: We asked our staff and some frequent contributors to write a short commentary on something that they had been thinking about in 2014. We gave everyone carte blanche. What follows is a collection of extremely varied, often very personal insights into how the planet impacted each individual.

I wish I could remember all the things I've forgotten

Thu, 30 Oct 2014 13:27:49 -0400

Credit: Kathleen Cantner, AGI.

Editor’s Note: We asked our staff and some frequent contributors to write a short commentary on something that they had been thinking about in 2014. We gave everyone carte blanche. What follows is a collection of extremely varied, often very personal insights into how the planet impacted each individual.

Beware the list that skews your view

Thu, 30 Oct 2014 12:58:57 -0400

Credit: ©Shutterstock.com/ Thinglass, Kathleen Cantner, AGI.

Editor’s Note: We asked our staff and some frequent contributors to write a short commentary on something that they had been thinking about in 2014. We gave everyone carte blanche. What follows is a collection of extremely varied, often very personal insights into how the planet impacted each individual.

Family trips, liberation from lists and other musings from 2014

Thu, 30 Oct 2014 12:49:03 -0400

Editor’s Note: We asked our staff and some frequent contributors to write a short commentary on something that they had been thinking about in 2014. We gave everyone carte blanche. What follows is a collection of extremely varied, often very personal insights into how the planet impacted each individual.

Rome's lead water pipes likely not a health risk

Mon, 06 Oct 2014 10:10:33 -0400

A lead pipe that supplied water to the Roman Baths in Bath, England. Credit: ©gds, CC BY-SA 2.0.

Ancient Rome was renowned for its vast and advanced plumbing system that brought freshwater to the city through viaducts and distributed it to the population via metal and clay pipes. But Rome’s civil engineers didn’t know about the neurological effects of lead in drinking water as we do today.

Massive icebergs scoured Arctic seafloor

Mon, 06 Oct 2014 10:04:25 -0400

In August 1990, the R/V Polarstern departed Tromsø, Norway, to investigate the ocean bottom bathymetry of the Fram Strait between Greenland and Svalbard. More than 20 years later, marine geologist Jan Erik Arndt and his colleagues at the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research in Bremerhaven, Germany, were reviewing data from the cruise when they discovered something new — the deepest evidence of iceberg scouring ever found.

Seismic friction causes fault iridescence

Mon, 06 Oct 2014 09:58:56 -0400

Geologist Mitch Prante examines thin hematite layers on a fault surface that recorded ancient seismicity in the Wasatch Fault Zone in Utah. Credit: Jim Evans.

Although iridescent spots on rocks in Utah’s Wasatch Fault Zone were first recognized two decades ago, scientists haven’t understood their origin, until now. New research shows that the iridescence appears on fault surfaces subjected to flash heating from friction and that the spots can provide clues to ancient seismic events.

Ohio millers imported French stone

Mon, 06 Oct 2014 09:44:57 -0400

Freshwater snail fossils were key in determining the French origins of millstones found in Ohio. Credit: Joseph Hannibal.

What’s the difference between France and Ohio? A few fossils. Common Ohio chert looks like a rock called French buhr found around Paris, except for a couple of fossils. Researchers say these fossils can be used to distinguish the Ohio flint from its often-misidentified French lookalike.

Seasonal ice-cover reduction throughout Arctic waters mapped

Mon, 06 Oct 2014 09:41:43 -0400

A new 35-year-long look at the extent of Arctic sea-ice seasons indicates that shortening sea-ice seasons are a consequence of Arctic warming. Credit: Claire Parkinson.

Nowhere is climatic warming more evident than in the Arctic. Arctic air has warmed almost twice as much compared to the global average in recent decades, and Arctic sea-ice extent has hit historic lows in the last decade.

Past penguin populations not dependent on ice extent

Sun, 05 Oct 2014 20:27:55 -0400

In the past, populations of Chinstrap and Adélie penguins (shown here) increased in number during times of gradual warming in Antarctica. Credit: ©Shutterstock.com/axily.

Penguins’ lives revolve around ice, so it seems they might be particularly vulnerable to changing ice conditions and ice loss. But a new study charting the rise and fall of penguin populations over the last 30,000 years suggests that past populations have actually increased during times of climate warming and retreating ice.

Clues to limestone weathering written in Western Wall

Sun, 05 Oct 2014 20:01:52 -0400

Builders and masons take note: When it comes to the durability of limestone, grain size matters. New research combining field and lab data shows that fine-grained limestone is more susceptible than its coarser-grained cousins to a one-two punch of chemical and mechanical weathering. The findings, which arose in part from observations of Jerusalem’s historic Western Wall, could have implications for Earth’s carbon cycle and landscape — as well as for architectural preservation.

Geologic Column: Geography as destiny: How glaciation led to the Civil War

Sun, 05 Oct 2014 19:11:01 -0400

credit: Michael Collier.

It intrigues me how geography — a product of dynamic processes shaping Earth’s surface — influences our lives, culture and even plays a hand in the affairs of nations. Take, for example, the last glacial maximum, which shaped parts of North America roughly 20,000 years ago, and in doing so contributed to factors that eventually led to the American Civil War.

Comment: IPCC faces challenges in communicating climate science

Fri, 03 Oct 2014 18:04:14 -0400

The latest report from the Intergovernmental Panel on Climate Change (IPCC), released piecemeal over the last year, reports “unequivocal” warming of the climate system due to increasing greenhouse gas concentrations, further emphasizing the need for global mitigation and adaptation schemes. But not everyone is ready to curtail carbon emissions, and the increasing clamor from skeptics and deniers — along with potential overstatements and even understatements by scientists — creates a polarized political environment that complicates efforts to communicate science effectively.

Energy notes: May 2013-2014

Fri, 03 Oct 2014 17:37:58 -0400

Credit: The American Geosciences Institute

U.S. Oil & Petroleum Imports (million of barrels per day)

Oil and petroleum imports data are preliminary numbers taken from the American Petroleum Institute’s Monthly Statistical Report. For more information visit www.api.org.

Mineral Resource of the Month: Zeolites

Fri, 03 Oct 2014 16:49:50 -0400

Robert Virta, a mineral commodity specialist for the U.S. Geological Survey, prepared the following information about the zeolite industry.

Chabazite is a common natural zeolite mineral. Credit: ©Didier Descouens, CC BY-SA 3.0.

Zeolites comprise a group of silicate minerals with very open crystalline structures that make them suitable for catalytic, ion exchange and molecular sieving applications. Aluminum, silicon and oxygen atoms are arranged in a 3-D framework of channels and cages. Water molecules and cations, such as calcium, sodium, potassium and magnesium, occupy these interconnected channels and cages. The cations can readily substitute for one another, and water molecules may be gained or lost without any major changes to the basic zeolite crystal structure.

Getting there and getting around Bali

Fri, 03 Oct 2014 10:56:59 -0400

Visitors to Bali arrive at the Ngurah Rai International Airport on the island’s southern side. No direct flights are available from the U.S.; most itineraries route through a major East Asian hub. To travel between Bali and the neighboring islands of Java or Lombok, you can either catch a short domestic flight (options include Garuda Indonesia and Lion Air) or take a short, though frequently rough, ferry ride.

Travels in Geology: Bali beckons

Fri, 03 Oct 2014 09:14:23 -0400

Bali is the top tourist destination in Indonesia — a vast archipelago of more than 18,000 islands stretching more than 5,000 kilometers between the Indian and Pacific oceans. Credit: ©Shutterstock.com/KKulikov.

In Indonesia — a vast archipelago of more than 18,000 islands stretching more than 5,000 kilometers between the Indian and Pacific oceans — Bali is the top tourist destination. The compact island boasts everything a visitor could want: copious sun, sand and surf, flavorful food and fruity libations, stunning sunsets, and verdant rice paddies tucked beneath misty mountains. It also has a number of geo-attractions, including hot springs and Indonesia’s first global geopark. But it’s the engaging, friendly and colorful Hindu culture — from the elaborate temples and dance performances to the ubiquitous religious offerings — that makes Bali such a vibrant and exotic destination. It was a requisite side trip for our family on a recent sabbatical in Australia.

Tiny ants are heroic weathering agents

Thu, 02 Oct 2014 14:28:59 -0400

Over geologic timescales, weathering of silicate minerals — which account for more than 90 percent of all crustal rocks on Earth — plays a significant role in decreasing carbon dioxide in the atmosphere, as carbon dioxide is consumed in chemical weathering reactions and the resultant carbonate becomes sequestered in the form of limestone and dolomite.

Can renewable energy and desalination tackle two problems at once?

Thu, 02 Oct 2014 13:31:03 -0400

Credit: ©Shutterstock.com/Pati Photo.

Over the past four years, a record-setting drought has impacted Texas, the second-most populous state in the U.S. The drought started in October 2010, and 2011 was the driest year on record for Texas, with an average of less than 40 centimeters of rain falling across the state. Today, more than 60 percent of the state is still experiencing some degree of drought, leaving reservoirs less than two-thirds full and impacting more than 15 million people. Stories of dry riverbeds and cities using their wastewater as a source for drinking water fill the headlines. Meanwhile, the state has continued to grow faster than all but two other parts of the U.S. (North Dakota and the District of Columbia), and electric grid operators worry about meeting demand.

Colorado River Basin sees severe groundwater depletion

Thu, 25 Sep 2014 13:10:13 -0400

Over the past 14 years, the Colorado River Basin has experienced its worst drought since precipitation records have been kept, starting in the 1960s. The basin supplies water used for agriculture and in households in seven states, affecting more than 40 million people. In a study recently published in Geophysical Research Letters, researchers have found that the reservoirs that store water in the basin are at record low levels. What’s more, the research shows that in addition to shrinking reservoirs, groundwater is being depleted much faster than previously thought, which could have major implications for the region’s future water security.

Bare Earth Elements: Search the seafloor firsthand (and live!)

Thu, 25 Sep 2014 11:38:35 -0400

If you’ve ever wanted to take a dive into the ocean depths and explore the seafloor below the waves, but just haven’t had the time (or financing) to build your own deep-sea submersible, here’s another solution. NOAA’s 68-meter Okeanos Explorer — the only federally funded ship dedicated to “solely to exploration” — is currently trolling the Atlantic Ocean on the three-week third leg of a mission dubbed “Our Deepwater Backyard: Exploring Atlantic Canyons and Seamounts 2014," and it’s offering to take guests along for part of the ride.

On the Web: Personalizing drought data with digital tools

Thu, 04 Sep 2014 14:25:31 -0400

The National Drought Mitigation Center works with federal agencies to produce a weekly map called the Drought Monitor, which displays the most recent data gathered on drought across the U.S.

One of the hardest parts of hazard mitigation is communicating risk to the public. With drought, people feel the heat while it’s happening but understanding how the current drought fits into past trends — and their implications for the future — is harder to grasp. Now, several online tools are available to help the public and decision-makers look at drought data.

Ice (Re) Cap: October 2014

Wed, 03 Sep 2014 09:12:25 -0400

Arctic permafrost, or thermokarst, lakes like these release methane, but new research suggests that on millennial timescales, they act as net carbon sinks as decaying organic matter is buried in lake sediments. Credit: UAF/Katey Walter Anthony.

From Antarctica to the Arctic; polar caps, permafrost and glaciers to ocean-rafted sea ice; and burly bears to cold-loving microbes, fascinating science is found in every nook and crevasse of Earth’s cryosphere, and new findings are announced often. Here are a few of the latest updates.

Acid rain recovery in the Northeast

Wed, 03 Sep 2014 09:06:09 -0400

Lakes in the Northeastern U.S. are showing some geochemical signs of recovery from acid rain. Credit: ©Paul D. Lemke.

Four decades after the passage of the Clean Air and Clean Water Acts, the acid rain that plagued the Northeast is still diminishing. The amount of sulfate and nitrate found in Northeastern lakes is not only declining, but the decrease has been speeding up, according to a long-term study recently published in Environmental Science & Technology.

For cloud formation, a little aerosol goes a long way

Wed, 03 Sep 2014 08:33:16 -0400

Clouds play a starring role in creating and controlling climate, but cloud physics are notoriously difficult to model, leaving wide gaps in understanding how cloud conditions have changed since the pre-industrial era. A new study looking at pristine regions of the sky in the South Pacific is shining some much-needed light on how particulate air pollution interacts with water vapor to form clouds.

Alaskan megathrust fault more active under Kodiak

Wed, 03 Sep 2014 08:12:33 -0400

This road along Womens Bay on Kodiak Island is in an area that subsided nearly 2 meters during the 1964 earthquake. Credit: U.S. Geological Survey Photographic Library.

In 1964, a magnitude-9.2 earthquake ruptured two segments of the Alaskan megathrust fault along more than 900 kilometers from Prince William Sound to Kodiak Island. Historical and paleoseismic evidence has hinted at previous events in this region in 1788 and about 1100, and now a team working on Kodiak Island has found clues of another large event that struck about 500 years ago. The find makes the recurrence interval for the tsunami-producing fault much shorter, potentially increasing the earthquake and tsunami hazard profile, not only for Alaska, but also Hawaii and California.

First building blocks in Oahu found

Wed, 03 Sep 2014 08:05:38 -0400

Oahu is the third-largest and most populated of the Hawaiian Islands. Credit: NASA.

The Hawaiian Islands that jut above the waves are merely the tops of a string of towering volcanoes known as the Hawaiian-Emperor seamount chain. These mountains have formed flow by flow, eruption by eruption, over the past 28 million years as the Pacific Plate moves over a hot spot in the mantle.

Shallow crust magma with a dash of salt and peperite

Tue, 02 Sep 2014 13:49:51 -0400

A mafic dike (right) cuts across a salt formation, exposed in the Herfa- Neurode Mine in Germany. The bulbous, pillowy peperite (center, left) formed when a sill intruded carnallite salt, causing water loss and instability in the salt. Credit: Nick Schofield.

Magma and salt are not often paired on the menu of geology. But, occasionally, the two do mix — with surprising results. Researchers explored these interactions in a new study, the first to examine how magma emplacement occurs in salt formations.

Methane lingered after Gulf blowout

Tue, 02 Sep 2014 13:42:43 -0400

Between April 20, 2010, when BP’s Macondo oil well blew out, and July 15, when the well was finally capped, more than 4 million barrels of oil were released into the Gulf of Mexico. Along with it came up to 500,000 metric tons of natural gas, mostly methane. Previously, researchers tracking the fate of those chemicals and their impacts on the Gulf of Mexico ecosystem estimated that most of the methane had been consumed by methane-oxidizing bacteria by the end of August 2010.

Boron proxies detail past ocean acidification

Tue, 02 Sep 2014 13:33:17 -0400

Aboard the drillship JOIDES Resolution, Don Penman and colleagues examine ocean floor sediments containing geochemical clues about the Paleocene-Eocene Thermal Maximum. Credit: John Beck.

Pockmarked plankton shells and dead coral are becoming the hallmark images of ocean acidification. But this isn’t the first time seawater has dropped on the pH scale. Based on models of seawater chemistry, the ocean acidity during the Paleocene-Eocene Thermal Maximum (PETM), beginning about 56 million years ago, is the closest-known analog to today. Now, researchers using boron proxies preserved in microfossils to reconstruct surface-ocean chemistry suggest that acidification was more extensive and lasted longer than previously thought, although the PETM conditions still don’t outpace the current rate of ocean acidification.

Climate impacting a few of our favorite foodstuffs

Tue, 02 Sep 2014 13:15:16 -0400

Nectarine trees, shown here in an orchard near Traver, Calif., and other fruit and nut trees are threatened by a lack of "fog days." Credit: ©Nate Gray, CC BY-NC-SA 2.0.

Less fog means trouble for Central Valley fruits and nuts

Researchers have found that the number of foggy winter days in California’s agriculture-heavy Central Valley has dropped 46 percent on average over the past three decades. Fog shields the valley from sunlight and contributes to the amount of “winter chill” — the amount of time spent between zero and 7 degrees Celsius during winter dormancy — that fruit and nut trees there experience. Sufficient winter chill is necessary for buds, flowers and fruit to develop properly, and although winter chill has previously been observed to have decreased since the 1950s, no one had conducted a long-term analysis of fog occurrence trends in the area, according to Dennis Baldocchi and Eric Waller of the University of California at Berkeley.

Seeing beneath Greenland's ice

Tue, 02 Sep 2014 13:07:43 -0400

Save the handful of Vikings who settled an ice-free stretch of Greenland’s southwest coast during the Medieval Warm Period a millennia ago, few humans have ever laid eyes on even a fraction of the land that lies below Greenland’s 1.7-million-square-kilometer ice sheet. Now, courtesy of a new model, scientists are seeing a detailed view of the topography underlying the ice sheet, which is an important control on the flow and discharge of ice into the ocean.

Of char and carbon: The story of a buried soil

Tue, 02 Sep 2014 12:43:55 -0400

Erosion on the U.S. Great Plains reveals a buried, carbon-rich layer of fossil soil. Researchers recently found that buried fossil soils contain significant amounts of black carbon. Credit: Joseph Mason.

The so-called Brady soil — a dark horizon up to a meter thick that underlies much of Kansas and Nebraska — is widespread but often unseen. The layer is a paleosol, or fossil soil, that formed about 15,500 to 13,500 years ago when the region was a stable grassland built atop dunes of thick, wind-blown loess. That changed when the Laurentide Ice Sheet retreated and dunes swallowed the grasslands.

Calculating America's energy landscape

Tue, 02 Sep 2014 10:04:25 -0400

Large concentrated solar power plants, like this one in the Mojave Desert, have big a footprint on landscapes. Credit: Alan Radecki.

Studying the landscape-scale impact of energy development, especially renewable energies, requires working at the interface where policy, business, activism, scientific research and stakeholders overlap. But determining broad-scale impacts comes down to having solid data — on key species, slope aspect, transmission distance and more — to understand and predict what happens on energy landscapes. Collecting, analyzing and sharing such data was the focus of several symposia at last summer’s North America Congress for Conservation Biology meeting in Montana.

Benchmarks: October 10, 1913: Atlantic and Pacific waters meet in the Panama Canal

Tue, 02 Sep 2014 08:50:45 -0400

On Oct. 10, 1913, U.S. President Woodrow Wilson pressed a button in his Washington, D.C., office. At that moment, more than 6,400 kilometers away, about seven metric tons of dynamite exploded, clearing the final obstruction in the Panama Canal. Deep within the Culebra Cut, waters from the Atlantic Ocean finally met waters from the Pacific Ocean, marking the end of major construction on the 77-kilometer-long canal.

Geologic Column: Combining art and geology in the sand

Tue, 02 Sep 2014 08:45:27 -0400

Credit: Chris Hansen.

Every summer, millions of people descend on beaches, many intent on building sand sculptures — some even with the hopes of winning fame or fortune. Once upon a time, sculptures made of sand were mostly castles, built by children and families on summer vacations to the beach. Today, sand sculpting is also a serious business, with competitions, prize money, festivals, corporate promotional campaigns, organized team-building exercises, and entries in the Guinness Book of World Records for traits including the tallest (more than 10 meters high) and longest (more than 10 kilometers long) sculptures. The subjects range far beyond castles: 3-D representations of historical artwork, and abstract designs like giant eyeballs aren’t unusual. However, castles continue to be a mainstay of the medium. There’s something about a moat that just makes sense on the beach.

Comment: Building sanctuaries to increase civilization's resilience

Tue, 02 Sep 2014 08:35:55 -0400

Credit: ©Callan Bentley, 2014.

Asteroid impacts, supervolcano eruptions, global pandemics, nuclear war and cyberterrorism are a few examples of scenarios that could cripple or destroy the very foundations of our civilization, leading to a widespread loss of infrastructure, knowledge, population and cultural artifacts. These losses would make recovery difficult or impossible. But instead of wringing our hands and preparing for a potential reversion to the Dark Ages or worse, perhaps humanity can invest in its future by building archival sanctuaries to safeguard civilization in the event of catastrophe.

Energy Notes: April 2013 - 2014

Tue, 02 Sep 2014 08:28:57 -0400

Credit: The American Geosciences Institute.

U.S. Oil & Petroleum Imports (million of barrels per day)

Oil and petroleum imports data are preliminary numbers taken from the American Petroleum Institute’s Monthly Statistical Report. For more information visit www.api.org.

Mineral Resource of the Month: Vermiculite

Tue, 02 Sep 2014 08:18:09 -0400

Arnold O. Tanner, a mineral commodity specialist for the U.S. Geological Survey, compiled the following information on vermiculite, which is used in construction and horticulture.

Vermiculite comprises a group of hydrated, laminar magnesium-aluminum-iron silicate minerals resembling mica. They are secondary minerals, typically altered biotite, iron-rich phlogopite or other micas or clay-like minerals that are themselves sometimes alteration products of amphibole, chlorite, olivine and pyroxene. Vermiculite deposits are associated with volcanic ultramafic rocks rich in magnesium silicate minerals, and flakes of the mineral range in color from black to shades of brown and yellow. The crystal structure of vermiculite contains water molecules, a property that is critical to its processing for common uses.

Getting there and getting around in Tucson

Tue, 02 Sep 2014 08:08:15 -0400

Both Phoenix and Tucson are good arrival points for exploring southeastern Arizona, but it’s best to base yourself in Tucson to visit the attractions described here. You will need a car to get around the area; if you choose to fly in, you can rent a vehicle at either city’s airport. Tucson is located about 180 kilometers south of Phoenix on Interstate 10.

Searching the stars

Tue, 02 Sep 2014 08:03:13 -0400

The lights of Tucson are visible from the observatory at Kitt Peak. Credit: ©Shutterstock.com/John A. Davis.

Thanks to its dry climate and soaring peaks, the Tucson region offers some of the best night-sky viewing in the world. Perched high in the Baboquivari Mountains, on the Tohono O’odham Reservation about 90 kilometers southwest of Tucson, Kitt Peak National Observatory hosts the world’s largest collection of research telescopes. It is home to 24 optical scopes, including the world’s largest solar telescope, and two radio telescopes. Guided tours are offered three times a day, or you can pick up a map at the gift shop and visit three large telescopes on your own. From Sept. 1 through July 15, weather permitting, Kitt Peak also offers popular nightly observing programs by reservation only; see www.noao.edu/outreach/nop/ for details. Mount Graham International Observatory (http://mgio.arizona.edu) and Mount Lemmon SkyCenter (http://skycenter.arizona.edu/) also offer evening stargazing programs.

Down to Earth With: Kerry Sieh

Fri, 29 Aug 2014 12:09:58 -0400

After more than 30 years as a professor and researcher at Caltech, earthquake geologist Kerry Sieh (pronounced “sea”) surprised his colleagues when he pulled up stakes in 2008 for a rare opportunity in Southeast Asia to be the founding director of the Earth Observatory of Singapore.

Travels in Geology: Winter sun and tectonic tales in Tucson

Fri, 29 Aug 2014 11:58:31 -0400

Late last March, seeking warm sun and a verdant landscape after a cold, snowy Colorado winter, our family headed south during the spring school break to the lowest-elevation place we could easily drive to in a day or two: Tucson. Hosting Saguaro National Park, the Arizona-Sonora Desert Museum and the largest concentration of astronomical observatories in the country, Tucson has the grand vistas, great hikes and learning opportunities we wanted.

How the Spanish invasion altered the Peruvian coast

Fri, 29 Aug 2014 11:39:17 -0400

When Francisco Pizarro landed in Peru in 1532, his band of Spanish conquistadors set off a chain of far-reaching consequences for the people and economics of western South America. A new study has found that the Spanish invasion also changed the shoreline of northern Peru, by actually ending a several-thousand-year cycle of anthropogenic alteration.

Santiaguito Volcano's clockwork behavior provides an exceptional laboratory

Fri, 29 Aug 2014 10:53:27 -0400

A large eruption as captured from the so-called "Paradise" campsite between the parent volcano, Santa María, and the Caliente dome. Credit: Benjamin R. Phillips.

Self-portrait of the author on the edge of the nearly 2-kilometer-high scarp of Santa María. Credit: Benjamin R. Phillips.

If Earth breathes, Santiaguito Volcano in the Western Highlands of Guatemala could be its mouth. Roughly every half hour, like volcanic clockwork, Santiaguito’s active Caliente lava dome expands, filling with gas from depressurizing magma below. Then it exhales, often explosively, and deflates. Over the course of a day, you could almost keep time by it.

Virtual water: Tracking the unseen water in goods and resources

Thu, 28 Aug 2014 13:57:57 -0400

China is a thirsty nation. Rapid economic growth and urbanization among its nearly 1.4 billion people in recent decades, as well as a growing taste for meat, have created an ever-growing demand for freshwater. And in the cities, industrial centers and farmlands of the more populous, more arid north, available resources — rivers, lakes and aquifers — are drying up.

Down to Earth With: Tom Malloy

Thu, 28 Aug 2014 12:23:38 -0400

In a century of mining, the Berkeley Pit and underground mines produced more than 290 million metric tons of copper ore and more than 635 million metric tons of waste rock. Credit: Drew Cramer.

Tom Malloy holds open a gate to the Diamond Mine headframe (behind) surrounded by mine waste. Credit: Brianna Mills.

Butte, Mont., is home to one of the nation’s largest Superfund sites — a 300-meter-deep lake of acidic, heavy metal-contaminated water known as the Berkeley Pit. As the reclamation manager of Butte-Silver Bow County, it’s Tom Malloy’s job to help clean it up.

Minimizing the risk

Fri, 22 Aug 2014 14:56:34 -0400

According to the Centers for Disease Control and Prevention, for those working in the field or living in the endemic area, it is very difficult to avoid exposure to the Coccidioides fungus, but there are precautions that can be taken.

Infrasound reveals lava lake levels

Thu, 21 Aug 2014 18:58:48 -0400

Only rarely can scientists get a view of the lava lake atop Villarrica volcano. Credit: Greg Waite.

The rises and falls of volcanic lava lakes are not easily tracked, especially when the lakes aren’t visible from crater rims. But recently, researchers found a way to monitor the lava lake at Chile’s Villarrica volcano using complementary methods to keep an eye on a feature they can’t always see.

All the world's glaciers in one global inventory

Tue, 19 Aug 2014 13:59:58 -0400

The Salmon Glacier on the border of Alaska and British Columbia is one of the nearly 200,000 glaciers in the world. Credit: Mary Caperton Morton.

Earth is home to about 198,000 glaciers, which have now all been mapped. The first global inventory of alpine glaciers, including their locations, extents, volumes and geographic outlines, has been assembled — a feat climate scientists and glaciologists hope will allow for better monitoring of the world’s ice.

New off-the-shelf aerial imaging technique trumps lidar

Tue, 19 Aug 2014 13:55:17 -0400

In recent years lidar has become the gold standard for people looking to make high-resolution aerial maps — from archaeologists studying ruins hidden beneath jungle canopies to engineers monitoring dams and levees. Although the technology has many useful applications, it’s often prohibitively expensive. Now, a new technique using an off-the-shelf digital camera is offering an inexpensive alternative for collecting 3-D aerial data.

New climate record challenges ideas about recent glaciations

Tue, 19 Aug 2014 13:13:21 -0400

Fossilized foraminifera from sediments at sites such as this one at Punta Maiata, Sicily, contributed to a new sea-level and deep-ocean temperature record dating back more than 5 million years. Credit: Eelco Rohling.

Predicting how a changing climate and rising sea levels might impact humans in the future requires an understanding of how Earth has changed in the past. So scientists are continually seeking more and better data to help illuminate earlier conditions.

R.I.P. Nereus

Tue, 19 Aug 2014 11:08:46 -0400

Nereus, the United States’ only full-ocean-depth submersible, was lost at sea on May 10, 2014. The unmanned and remotely operated vehicle was capable of reaching the hadal zone, the ocean region 6 to 11 kilometers deep, and was designed, built and operated by Woods Hole Oceanographic Institution (WHOI) in Massachusetts. Nereus was at a depth of 9,990 meters in the Kermadec Trench off New Zealand, the fifth-deepest ocean trench in the world, when it lost contact with researchers aboard the R/V Thomas G. Thompson. Debris later surfaced, which was recovered and determined to be the remains of the vessel. The debris indicated a catastrophic implosion, likely of one or more of the vehicle’s ceramic buoyancy spheres.

Nutrient runoff feeding Baltic Sea dead zone

Tue, 19 Aug 2014 11:04:52 -0400

Hypoxic (red) and anoxic (black) deep waters in the Baltic Sea extend over a far larger area today than they have historically. Credit: J. Carstensen et al. Proceedings of the National Academy of Sciences, 2014.

Low-oxygen, or hypoxic, deep waters now extend over an area of about 60,000 square kilometers in the Baltic Sea, a tenfold increase compared to 115 years ago, according to a recent study published in Proceedings of the National Academy of Sciences. The hypoxic zone has fluctuated substantially in that period, but much of the expansion has occurred in recent decades as a result of large inputs of nutrients like nitrogen and phosphorus from human activities such as agriculture, reported Jacob Carstensen of Aarhus University in Denmark and colleagues.

Mississippi sand still abundant

Tue, 19 Aug 2014 10:57:41 -0400

Rice University researcher Jeffrey Nittrouer on an exposed dune field in the Bonnet Carré spillway in Louisiana in July 2011. Nittrouer and colleagues found that about 40 percent of the sand being carried down the Mississippi River was diverted through the spillway during a flood diversion that year. Credit: J. Nittrouer/Rice University.

Flood control measures along the Mississippi River have likely saved countless lives, but the effects of upstream dams and containment on the river’s delta have been ecologically catastrophic: In the past 80 years, more than 5,000 square kilometers of wetlands along the Louisiana coast have been starved of vital sediment and drowned. Now, researchers have found that the lower river contains a significant reservoir of the sand needed to mitigate land loss at the river’s mouth — if it can be diverted downstream.

Natural arsenic levels in Ohio soils exceed regulatory standards

Tue, 19 Aug 2014 10:44:13 -0400

A new study in which all 842 soil samples taken in Ohio had more arsenic than recommended by the Environmental Protection Agency (EPA) raises the question of what to do when natural background levels in the environment exceed limits set to protect ecosystems and human health.

Africa's impact is one that even the dinosaurs would have seen coming

Tue, 12 Aug 2014 18:37:46 -0400

An artist's rendering of an asteroid impacting Earth. Credit: NASA/Don Davis.

The crater left by the infamous Chicxulub asteroid responsible for finishing off the dinosaurs about 65 million years ago, was more than 19 kilometers deep and 177 kilometers in diameter. Those dimensions correspond to a huge energy release estimated at 100 teratons of TNT, but that’s puny compared to an impact that struck South Africa’s Barberton Greenstone Belt about 3.26 billion years ago. Now, researchers have estimated just how big that massive asteroid was and the catastrophic effect it might have had on Earth and its budding plate tectonic system.

Floating nuclear plants may be safer from tsunamis

Fri, 08 Aug 2014 12:16:33 -0400

Credit: Kathleen Cantner, AGI.

On March 11, 2011, a magnitude-9 earthquake just off the coast of Tohoku, Japan, set off a devastating tsunami that swamped the Fukushima Daiichi nuclear plant complex on the coast northeast of Tokyo. Backup generators failed, triggering nuclear meltdowns in three reactors that could no longer be cooled.

Sunken logs a delicacy for ocean bottom-feeders

Fri, 08 Aug 2014 12:03:23 -0400

Craig McClain examines a piece of wood retrieved after five years on the bottom of Monterey Canyon at a depth of 3,200 meters. The holes in the wood were made by boring clams. Credit: ©2013 MBARI.

Wood isn’t often on the menu for deep sea-dwelling critters, but for some species, there’s nothing like a tasty tree stump for dinner. Five years after leaving bundles of Acacia wood 3,200 meters deep at the bottom of Monterey Canyon off the central California coast, biologists retrieved the bundles with a remotely operated vehicle and found that some hosted diverse colonies of organisms.

Volcanic ash feed southern ocean plankton

Fri, 08 Aug 2014 11:54:55 -0400

Technicians aboard the British RRS James Cook retrieve a seawater sampling device in the Southern Ocean. Credit: Gideon Henderson.

Ash plumes from volcanoes in South America and elsewhere may spur large blooms of plankton in otherwise barren parts of the Southern Ocean, but maybe not for the reason scientists have suspected, according to a new study. Such blooms are of interest because they consume atmospheric carbon dioxide, although their overall effect on climate remains far from clear.

The subcontinent's sturdy mammals

Fri, 08 Aug 2014 11:40:11 -0400

The spotted deer, or chital (Axis axis), has inhabited parts of India for most of the last 200,000 years. Credit: ©Yathin S. Krishnappa, CC BY-SA 3.0.

India is home to some hardy mammals, according to a new study in Proceedings of the National Academy of Sciences. Researchers reported that 20 of 21 mammalian taxa identified from fossils found in southern India have survived on the subcontinent over at least the last 100,000 years, with some lineages stretching back twice that long.

Extra rib may be sign of mammoth decline

Fri, 08 Aug 2014 11:36:28 -0400

High rates of a congenital defect in woolly mammoths may offer evidence that inbreeding and environmental stress contributed to the animals’ demise during the Late Pleistocene, according to a new analysis of fossil mammoth neck bones.

South American fossils offer revised view of Gondwana assembly

Fri, 08 Aug 2014 11:31:25 -0400

An Archaeonassa trace fossil identified in carbonate rocks from the Bambuí Group in Brazil is thought to have been left by an organism during the Late Ediacaran. Credit: Lucas Warren.

Fossils of a known age have been found for the first time in rocks in Brazil that, although long-studied, had previously eluded scientists’ attempts to pinpoint their age. The discovery of the marine animals dates the rocks to 550 million years ago, researchers say, offering important insights into the geological evolution and timing of the assembly of the former supercontinent Gondwana.

Warm river water melted Arctic sea ice

Fri, 08 Aug 2014 11:10:25 -0400

Sea-ice extent and open-water surface temperatures in the Beaufort Sea changed dramatically between June 14 (left) and July 5, 2012 (right), during which the barrier of "landfast" sea ice blocking the mouth of the Mackenzie River (left image, bottom) gave way. Credit: NASA.

In September 2012, the area of the Arctic Ocean covered by sea ice was the smallest on record since satellite monitoring began in 1979. Several factors are thought to have contributed to that summer’s diminished ice, including a large cyclone in August that brought warmer ocean waters into the area and broke up the ice and a longer-term trend of thinning and weakening sea ice. Now, researchers have found that at least one large burst of warm freshwater into the Arctic earlier in the summer probably played a role as well.

Longer season for Rocky Mountain wildflowers

Fri, 08 Aug 2014 10:56:22 -0400

The Rocky Mountains. Credit: Public domain.

A nearly 40-year study of Rocky Mountain wildflower phenology has found that almost two-thirds of species have changed their blooming patterns in response to climate change. Flowers are blooming earlier each spring and lasting longer each fall, but not all species are reacting similarly.

Acid oceans followed Chicxulub impact

Fri, 08 Aug 2014 10:36:16 -0400

The proposed mechanism by which the oceans could have been acidified within days after the Chicxulub impact 65.5 million years ago. Credit: Kathleen Cantner, AGI.

Within days after the massive Chicxulub impact that ended the Cretaceous Period 65.5 million years ago, a deluge of acid rain may have turned Earth’s ocean surfaces into suddenly inhospitable homes for a multitude of microorganisms, ultimately pushing them to extinction, according to a new study.

The Bay Area's next 'big one' could strike as a series of quakes

Thu, 07 Aug 2014 12:58:42 -0400

Credit: drumbo/www.flickr.com via Creative Commons.

The San Andreas Fault is the most notorious fault in the San Francisco Bay Area, but other principal faults could also pose a significant threat to the region. Credit: Kathleen Cantner, AGI.

Californians are bracing for when the San Andreas Fault unleashes the next “big one,” but a new study looking at the paleoseismic history of the San Francisco Bay Area suggests that accumulated stress could also be released in a series of moderate to large quakes on satellite faults, rather than by a single great event on the San Andreas.

Valley fever's deadly history

Thu, 07 Aug 2014 12:52:06 -0400

The earliest recorded case of coccidioidomycosis was documented in Argentina in 1892, when a soldier was diagnosed with what was first thought to be an infection of coccidia — parasitic protozoans, like cryptosporidium and toxoplasma, that infect the intestines of animals, including chickens, cows, dogs and cats. The soldier lived with the disease for 11 years, during which time his doctors realized it was not caused by a protozoa but by a fungus. The name, however, stuck.

Valley Fever an occupational hazard for geoscientists

Thu, 07 Aug 2014 12:46:23 -0400

Valley Fever is a sometimes-fatal disease caused by a soilborne fungus contracted by inhaling spores in airborne dust. Arizona, where this dust storm occurred in 2011, is a highly endemic area. Credit: ©Alan Stark, CC BY-SA 2.0.

Geoscientists should take precautions against contracting Valley Fever — a sometimes-fatal infection with no known cure and no vaccine that is caused by a soilborne fungus, said James A. Jacobs, a California-based consulting hydrogeologist, at the annual meeting of the American Institute of Professional Geologists last year.

How to keep the flows out: Build a wall

Thu, 07 Aug 2014 11:47:40 -0400

The upper northern slopes of Mauna Loa are a painter’s palette of red, brown and black lava rocks. A cluster of scientific buildings composing the Mauna Loa Observatory and Solar Observatory stands out with their reflective white and silver rooftops against the Mars-like backdrop.

Kilauea vs. Mauna Loa

Thu, 07 Aug 2014 11:40:15 -0400

In the 19th century, Mauna Loa was the most active volcano in the world. Today, Kilauea is the star. Tourism agencies, journalists, civil defense, and even U.S. Geological Survey Hawaiian Volcano Observatory (HVO) geologists have played a role in funneling public attention toward the Big Island’s youngest volcano. Consequently, some people ignore the other volcanic threats on the island, including Mauna Loa. Without knowing the differences between the two volcanoes, people walk away thinking that if they have seen and interacted with one, they know them all.

Changing the landscape: Geoscientists embrace 3-D printing

Thu, 07 Aug 2014 09:59:19 -0400

Credit: Kathleen Cantner, AGI.

Franciszek Hasiuk prints T. rex skulls in Iowa State University's school colors using a 3-D printer. He uses these and other printed "fossils" for teaching and outreach. Credit: Franciszek Hasiuk.

In a modest, low-slung room tucked in the back of Oregon State University’s Pacific Slope Archaeological Laboratory, a small box sits quietly buzzing on a countertop and hiccuping each time the mechanical arm inside abruptly changes direction. Behind the box’s clear walls, an object has started to take shape. It looks something like a lumpy plastic pancake, but closer inspection reveals sharp edges and a scalloped surface. It is actually a half-finished replica of an arrowhead excavated from Cooper’s Ferry, Idaho, an idyllic spot along the Salmon River inhabited by early North Americans 13,000 years ago. The box producing it — a 3-D printer called a Replicator 2, designed by the Brooklyn-based company, MakerBot — is much newer.

Getting there & getting around the Aussie Outback

Mon, 04 Aug 2014 12:34:20 -0400

The Red Center’s gateway airports are Alice Springs and Ayers Rock/Uluru. Neither hosts direct flights from the U.S. but both are well connected to Sydney, Australia’s primary international arrival point, and other major Australian cities.

Distances in the Outback are vast; renting your own wheels is by far the most convenient way to get around, although petrol is very expensive (we paid up to US$8.25 per gallon). Both gateway airports offer a good selection of rental cars, including four-wheel-drive vehicles, from major international companies.

Travels in Geology: Aussie Outback Adventure

Mon, 04 Aug 2014 11:33:54 -0400

Australia, having experienced little recent tectonic activity, is the world’s lowest and flattest continent on average. But don’t take that to mean it’s geologically boring. It is this very quiescence that has ensured the preservation of a remarkable record of early-Earth events on the continent: from mineral grains only slightly younger than the planet itself, to a glacial event so severe that geologists call it “Snowball Earth,” to an unparalleled record of life’s early evolution. To see the ancient rocks that hold this record, you must leave the comparatively lush coastal strip — home to 90 percent of Australia’s population — and venture into the vast, arid interior wilderness known as the Outback.

Down to Earth With: Chris Strong

Mon, 04 Aug 2014 10:56:24 -0400

Chris Strong (right), the warning coordination meteorologist, and Steven Zubrick, science and operations officer, from the National Weather Service's Baltimore-Washington, D.C., forecast office after a winter weather briefing with White House staff. Credit: Chris Strong.

Being a weatherman is sometimes a thankless job, particularly when forecasts don’t pan out as expected. But the two-fold task of meteorologists — predicting the course and severity of impending weather events, and clearly communicating those predictions to a broad audience — is a vital one. This is especially true when you’re part of the group that so many people, including other forecasters, turn to as the primary source for weather information and insight: the National Weather Service (NWS).

Benchmarks: September 1, 1957: Fossil Cycad National Monument is dissolved

Mon, 04 Aug 2014 10:29:17 -0400

On Sept. 1, 1957, with the stroke of a pen, the U.S. Congress declared Fossil Cycad National Monument in the Black Hills of South Dakota to be no more. At one time, the site held the world’s largest collection of rare fossil cycad-like plants that thrived during the Cretaceous. Over the years, mismanagement, vandalism and theft left the site barren of fossils — the site never had a staff or visitor center, and was never opened to the public. The site’s initial designation as a national monument, in October 1922, had been brought about by the crusading of one man, Yale University paleobotanist George R. Wieland; in the end, he was also responsible for its demise.

Energy Notes: March 2013-2014

Mon, 04 Aug 2014 10:11:15 -0400

Credit: The American Geosciences Institute.

U.S. Oil & Petroleum Imports (million of barrels per day)

' Oil and petroleum imports data are preliminary numbers taken from the American Petroleum Institute’s Monthly Statistical Report. For more information visit www.api.org.

Mineral Resource of the Month: Arsenic

Mon, 04 Aug 2014 10:02:57 -0400

The most common arsenic-containing minerals are arsenopyrite, realgar and orpiment (shown here). ©Elke Wetzig, CC BY-SA 3.0.

George Bedinger, mineral commodity specialist for the U.S. Geological Survey, prepared the following information on arsenic.

Geologic Column: How T. rex got its street cred back

Mon, 04 Aug 2014 09:50:15 -0400

©J.M.Lujit, cc-by-2.5-nl licentie van auteur.

You wake up hungry in the middle of the night and remember that chunk of Spam in the refrigerator. You sneak down, ease open the fridge door and find that, embedded in said Spam, is a set of dentures. How do you react? With a Brando-esque utterance of “the horror, the horror”? Of course not; you have scientific smarts to fall back on.

Comment: Energy 360: Let science speak, not agendas

Mon, 04 Aug 2014 09:13:51 -0400

Credit: ©shutterstock.com/MilaSupinskaya.

Ideally, science is objective and without bias. But realistically, some bias, in the form of predetermined inclination, is unavoidable. Unfortunately, science can be used naïvely, without understanding its limitations, or shrewdly, to manipulate an issue. Such use of science by nonscientists, often to gain political advantage, is worrisome. More troubling is when scientists themselves become activists. There are times when scientists feel morally or ethically obligated to speak out, and they are, of course, free to do so. But without proper context, disclosure of bias and potential conflicts of interest, the risk is great that politicians, the media and the public will have trouble distinguishing where scientific objectivity stops and activism begins. Thus, transparency is essential.

Comment: The search for clarity on climate change

Thu, 31 Jul 2014 12:34:41 -0400

Credit: ©Shutterstock.com/JohnWollwerth

Straightforward scientific conclusions about climate change often fail to reach policymakers and the broader society. Climate scientists need to revise their communication strategies to close the vast gap in understanding that persists between what is known about climate change and how the public perceives the issue.

Energy Notes: February 2013-2014

Tue, 29 Jul 2014 13:55:26 -0400

Credit: The American Geosciences Institute

U.S. Oil & Petroleum Imports (million of barrels per day)

' Oil and petroleum imports data are preliminary numbers taken from the American Petroleum Institute’s Monthly Statistical Report. For more information visit www.api.org.

Mineral Resource of the Month: Peat

Tue, 29 Jul 2014 13:20:33 -0400

Lori E. Apodaca, mineral commodity specialist for the U.S. Geological Survey, prepared the following information on peat, which is used primarily for horticulture in the U.S.

Although most peat is used in horticultural applications, it is still cut into blocks and used as fuel, as shown here at a peat bog in Ireland. Credit: ©markjhandel/CC-BY-2.0.

Peat is an organic material formed from the incomplete decomposition of plant matter under anaerobic conditions. Over thousands of years, layers accumulate at a rate of about 0.5 to 1 millimeter per year. Water sources and chemistry influence the type and decomposition of vegetation in peat ecosystems like bogs and fens, from which peat is harvested.

A real rift in the midcontinent

Mon, 28 Jul 2014 18:44:06 -0400

Analogs for the various life stages of the Midcontinent Rift can be seen today. The early rift looked like today's East African Rift, with major plates pulling apart, separated by microplates. At middle age, it was similar to the West Central African Rift, where faulting during the opening of the South Atlantic during the Mesozoic created four microplates. Looking at the progression could help geologists understand how the Midcontinent Rift evolved, says co-author Seth Stein, a geophysicist at Northwestern University. Credit: Kathleen Cantner, AGI.

But now, Carol Stein of the University of Illinois at Chicago and her colleagues have offered a new possibility. Stein and colleagues suggest the Midcontinent Rift was related to the breakup of a supercontinent and to the early stages of a young ocean basin opening — similar to what is happening today in East Africa’s Great Rift Valley — that preceded the Atlantic. The findings could have implications for how geologists view early plate tectonics, and cast new light on the New Madrid Fault Zone, formed 500 million years later and home to earthquake-producing faults in Arkansas, Missouri and Tennessee that seriously rocked the region in 1811 and 1812.

Books: The once and future San Andreas Fault

Mon, 28 Jul 2014 13:04:35 -0400

"Earthquake Storms: The Fascinating History and Volatile Future of the San Andreas Fault," by John Dvorak, Pegasus, 2014, ISBN: 978-1605984957.

One of the most famous pictures of the San Andreas Fault — taken by G.K. Gilbert, the pioneering geologist whose late-19th century insights into faults and the earthquake cycle were close to prescient — shows a woman standing next to the ruptured fault immediately after the 1906 earthquake.

Moving cars could help gauge rainfall

Tue, 22 Jul 2014 18:53:00 -0400

Could sensors in cars one day supplant scientific rain gauges? Credit: ©Shutterstock.com/CBCK

Accurate and timely rainfall measurements are crucial for the design of drainage systems, dams and other modern infrastructure. But rain gauges are often spread too sparsely to provide the necessary coverage in densely populated regions. In parts of Germany, for example, gauges equipped to make hourly readings are especially scarce — just one per 1,800 square kilometers. To help fill in the gaps, researchers at the Leibniz University of Hannover are developing an idea they call “RainCars” — using moving cars to measure rainfall.

Ocean waves explain which La Niña events will linger

Fri, 18 Jul 2014 18:00:40 -0400

El Niño years are characterized by warm conditions in the eastern tropical Pacific while in La Niña years, like 2007 (shown here), the tropical Pacific is cool. Credit: NASA.

Many La Niña events last just one season, but historical records reveal that nearly half linger for two years or more, a phenomenon scientists have long struggled to explain. Now, new research has identified a potential mechanism behind such enduring La Niñas that may provide a blueprint for the kinds of long-range predictions needed to mitigate the economic impacts of associated events like the devastating Texas drought.

Ancient seawater found in Chesapeake Bay impact crater

Fri, 18 Jul 2014 17:38:17 -0400

When the bolide struck in the Late Eocene, it shattered the bedrock, truncated aquifers and left a crater roughly twice the size of Rhode Island and nearly as deep as the Grand Canyon. The resulting structural low is likely responsible for the formation of the Chesapeake Bay.

On the Web: Ka-pow! Superhero short films get kids thinking about climate change

Fri, 11 Jul 2014 15:36:44 -0400

The Green Ninja may sound like a spin-off of the “Power Rangers,” the live-action children’s television series featuring color-coded superheroes. But there’s a little less punch and a lot more thought going into this YouTube science show for kids.

Striped pyrites link earthquakes to gold deposition

Thu, 10 Jul 2014 15:11:36 -0400

Researchers have linked pyrite in the Porgera gold mine in Papua New Guinea to the so-called fault-valve process of gold deposit formation. Credit: Richard Farbelini.

Pyrite, or “fool’s gold,” is an iron sulfide mineral commonly found in hydrothermal ore deposits. In such deposits, gold atoms can substitute for iron in the structure of pyrite, so pyrite crystals in gold mines often contain portions of the precious metal. Eleanor Peterson, a student at the Australian National University (ANU) in Canberra, and her advisor, John Mavrogenes, an economic geologist also at ANU, analyzed pyrites from the Porgera mine in Papua New Guinea, where quartz veins in the Roamane Fault Zone host high-grade gold ores.

Desert dust influences monsoon rains

Thu, 10 Jul 2014 14:40:08 -0400

Dust storm over the Arabian Sea on January 13, 2013. Credit: Jeff Schmaltz, NASA, LANCE MODIS Rapid Response.

A team led by V. Vinoj of the Indian Institute of Technology in Bhubaneswar and Philip Rasch of the Pacific Northwest National Laboratory in Washington used satellite data and climate simulations to examine the relationship between desert dust levels over the Arabian Sea, West Asia and the Arabian Peninsula, and the intensity of the Indian summer monsoon. They found that desert-dust levels were positively correlated with the intensity of monsoon rainfall.

A watery surprise from Earth's depths: Mineral provides first direct evidence for water in mantle's transition zone

Thu, 10 Jul 2014 12:58:05 -0400

This half-centimeter-wide diamond contains a speck of ringwoodite, the first known water-bearing mineral from Earth's transition zone. Credit: Graham Pearson, University of Alberta.

Studies of seismic waves traveling through Earth have long suggested that the mantle is like a layer cake, with regions of differing composition. In a layer known as the transition zone, between depths of about 410 to 660 kilometers, much of the rock is thought to be composed of pressure-squeezed variants of the common mineral olivine. One of these hypothesized forms is ringwoodite, which forms blue, cube-shaped crystals. Ringwoodite synthesized in the lab under high pressure can contain up to 2 percent water by weight, suggesting the transition zone could hold massive amounts of water. But direct evidence of this water had been nonexistent as no one had observed ringwoodite from the mantle; the only naturally occurring specimens had come from meteorites.

Getting there and getting around the Causeway Coast

Tue, 01 Jul 2014 08:47:03 -0400

Left: Rathlin Island is famous for its seabirds, shipwrecks and seafood. Top right: Public pay phones are still a common sight in Northern Ireland. Bottom right: No need to carry a tent or lots of extra food on the Causeway Coast Way, but be sure to pack rain gear. Credit: all: Mary Caperton Morton.

To visit the Causeway Coast, fly into Dublin or Belfast and rent a car or take a bus to Ballycastle, Bushmills or Portstewart. During the summer tourism season, public buses run on a regular schedule up and down the coast. Accommodations are available in most of the small towns, ranging from high-end hotel rooms in Portstewart to quaint bed-and-breakfasts to budget hostels. More information on the Causeway Coast Kayak Association’s Port Moon Bothy hut can be found at: www.canoeni.com/canoe-trails/north-coast-sea-kayak-trail/access-point/port-moon.

The legend of Finn Maccool's Causeway

Tue, 01 Jul 2014 08:39:21 -0400

Credit: Mary Caperton Morton.

A long time ago, when giants ruled the Earth, a massive Irishman named Finn MacCool was challenged to a fight by the Scottish giant Benandonner. Now, as everybody knows, giants can’t swim, so MacCool, an expert mason and not one to back down from a fight, built a walkway of hexagonal stones across the North Channel to the coast of Scotland so the two behemoths could meet.

Between rocks and hard places

Tue, 01 Jul 2014 08:32:18 -0400

If you are interested in exploring Northern Ireland but are unsure about going it alone, the Geological Survey of Northern Ireland offers custom-guided landscape tours to any and all of Northern Ireland’s natural attractions, including the Causeway Coast, Mourne Mountains and Sperrin Mountains. Experienced guides will take you on half-day or all-day trips highlighting the region’s geology, history and folklore. The “Between Rocks and Hard Places” tours can be scheduled seven days a week, year-round, for groups of up to 29 people. For more information, email gsni@detini.gov.uk and see www.bgs.ac.uk/gsni/landscape.

Travels in Geology: Basalt cliffs and columns along Nothern Ireland's Causeway Coast Way

Tue, 01 Jul 2014 07:18:16 -0400

Sunset on the Giant's Causeway. The Causeway Coast Way runs along the cliffs above. Credit: Mary Caperton Morton.

Like its neighbor to the south, Northern Ireland is renowned for its green vegetation, but the rocks that underlie this part of the Emerald Isle are also legendary. The Antrim Coast famously hosts one of the most striking examples of columnar basalt in the world, the Giant’s Causeway, which, according to legend, was built by a brawling giant. Other local lore tells of island cave hideouts, shipwreck massacres and Viking sieges.

Crowdfunding spotlight

Mon, 30 Jun 2014 13:52:56 -0400

Science writers at Columbia University used Kickstarter funding to create a calendar of glamour shots of Columbia scientists, including Lisa Goddard and Kátia Fernandes of the International Research Institute for Climate and Society and Richard Seager and Jason Smerdon of Lamont-Doherty Earth Observatory. Credit: all: Charlie Naebeck.

NAME: Rebecca Fowler & Francesco Fiondella, science writers at Columbia University

Crowdfunding science: A new piece of the research grant puzzle

Mon, 30 Jun 2014 13:19:23 -0400

Credit: Kathleen Cantner, AGI

As a leading researcher in the field of atmospheric science, University of Washington scientist Dan Jaffe had never had trouble securing funding for his work on airborne pollutants. Over the past 20 years, he has been awarded more than $7 million dollars in grants from multiple government agencies, from NOAA and NASA, to the Environmental Protection Agency (EPA) and the National Science Foundation (NSF). That all changed when he wanted to study the effects of increased coal-train travel through his home state of Washington.

Energy Notes: January 2013-2014

Thu, 26 Jun 2014 11:07:37 -0400

Credit: The American Geosciences Institute.

U.S. Oil & Petroleum Imports (million of barrels per day)

Oil and petroleum imports data are preliminary numbers taken from the American Petroleum Institute’s Monthly Statistical Report. For more information visit www.api.org.

Mineral Resource of the Month: Niobium

Thu, 26 Jun 2014 10:44:26 -0400

U.S. Geological Survey mineral commodity specialist John F. Papp compiled the following information on niobium, also called columbium.

Niobium, also called columbium, is a transition metal with a very high melting point. It is in greatest demand in industrialized countries, like the United States, because of its defense-related uses in the aerospace, energy and transportation industries. Niobium is used mostly to make high-strength, low-alloy (HSLA) steel and stainless steel. HSLA steels are used in large-diameter pipes for oil and natural gas pipelines and automobile wheels.

Belugas, climate, mercury and cancer

Thu, 26 Jun 2014 10:41:37 -0400

White Whale or Beluga Whale (Delphinapterus leucas) from Churchill River near Hudson Bay (Canada). Credit: Ansgar Walk.

Scientists have such a good dataset from more than two decades of studying belugas in the Arctic that they can now use the data collected there to see what might be occurring in other populations of beluga whales, especially in the St. Lawrence Estuary. There, 20 percent of adult whales are dying of cancer in the digestive tract and liver, Raverty says, among the highest rates of cancer in any wild terrestrial or marine mammal. Thus, using the Arctic population of beluga as a control, scientists can investigate which environmental factors in the St. Lawrence region may be contributing to the spike in cancers there and elsewhere.

Geologic Column: Beyond geology, field camps teach teamwork and inspire leadership

Tue, 24 Jun 2014 16:44:31 -0400

A tent camp in the Chisos Mountains in Texas offers a temporary home for students during a regional geology field course run by the College of William and Mary. Credit: Jessica Ball.

For undergraduate geology students, field camp is a rite of passage. And the importance of the experience, in terms of properly training and preparing geoscience students to become geoscience professionals, should not be underestimated. Over the years, the number of geoscience field camps has declined substantially. This is unfortunate, but we have reason to hope that more schools will again start offering field camps soon.

Searching for evidence of ancient subduction

Mon, 23 Jun 2014 17:55:26 -0400

Metamorphosed volcanic rock of the Nuvvuagittuq supracrustal belt at Porpoise Cove in Quebec, Canada. Credit: Steve Mojzsis.

Scientists typically search for structural or geophysical indications that offer telltale signals of the locations of past subduction zones. Such visible evidence might include old fault planes preserved in rock or subsurface images (afforded by seismic data) of former plates now swallowed by the mantle. Without such evidence, however, scientists must depend only on isotopic ratios, trace element concentrations and other geochemical signals in very old rocks for clues about where and when the process operated. But such signals aren’t necessarily unique to subduction zone settings, and they can be blurred or obscured over geological time, thus complicating their interpretation.

Parasites spread across the Arctic under the 'new normal'

Mon, 23 Jun 2014 16:31:38 -0400

Researchers have found new pathogens in gray seal populations. Credit: U.S. Fish and Wildlife Service.

The spread of pathogens into new areas is a pressing issue, according to Michael Grigg, a molecular parasitologist with the National Institutes of Health in Bethesda, Md. He reported on his research at the annual meeting of the American Association for the Advancement of Science (AAAS) in Chicago in February.

Travels in Geology: Peru's petrified forest: The struggle to study and preserve one of the world's most remarkable fossil sites

Mon, 23 Jun 2014 10:53:18 -0400

Located approximately 2,800 meters high on a plateau in the Andes, Peru's petrified forest is exposed around the rim of a caldera-like basin. To the east and south of the basin, the Rio Chancay has sliced a deep canyon. Credit: Jean Schnell.

This log was lithified — preserving the rings and details of the tree's anatomy — 39 million years ago. Credit: Jean Schnell.

Tucked high in the Andes Mountains of northern Peru is a remarkable fossil locality: a 39-million-year-old petrified forest preserved in nearly pristine condition. With its existence unknown to scientists until the early 1990s — and its significance unbeknownst to villagers — this ancient forest hosts the remains of more than 40 types of trees, some still rooted, that flourished in a lowland tropical forest until they were suddenly buried by a volcanic eruption and a series of roiling torrents of mud and debris known as lahars.

Creationism comes to the county fair

Mon, 23 Jun 2014 10:24:00 -0400

You never know what you're going to find at the fair. Credit: ©iStockphoto.com/Lokibaho.

County fairs are opportunities to bring in those handsome Holsteins competing for Best Bessie, to sample foods that don’t normally belong on sticks and definitely shouldn’t be deep-fried, and to enjoy carnival rides and games with unfavorable odds. They’re also opportunities to get the attention of a lot of people. Just ask the exhibitors who pay for space to hawk their wares.

Pike's Peak

Mon, 16 Jun 2014 10:08:14 -0400

The 4,300-meter-tall peak that Zebulon Pike first spied in November 1806 was already known to Native Americans, as well as Spanish settlers, who called it El Capitán. Pike first dubbed it Grand Peak, but by the mid-19th century, the name Pike’s Peak (later Pikes Peak) had begun to stick.

Benchmarks: July 15, 1806: Zebulon Pike launches Southwest expedition

Mon, 16 Jun 2014 10:03:13 -0400

Brig. Gen. Zebulon Pike depicted during the War of 1812. Credit: Library of Congress.

Of America’s early 19th-century western explorers, Meriwether Lewis and William Clark typically garner the most attention. But there was a third military man who, along with a detachment of U.S. Army troops and volunteers, also trekked into the newly acquired reaches of the young United States in the same era: Zebulon Pike.

Geomedia: Books: The earth system symphony

Mon, 16 Jun 2014 09:24:32 -0400

Credit: Copyright Shutterstock.com/Vilainecrevette

"The Dance of Air and Sea: How Oceans, Weather, and Life Link Together," by Arnold H. Taylor, Oxford University Press, 2011, ISBN: 9780199565597.

The planet is a symphony played by the orchestral sections of the atmosphere, hydrosphere, geosphere and biosphere, each of which includes many instruments. However, teasing out the myriad relationships in the concerto that is the earth system is daunting. Not only do the scales involved range from planetary to microscopic, but our observational records are also relatively short, and some features are inherently chaotic. Just understanding the basics of any one of the major components can take a lifetime.

Getting there and getting around Tajikistan

Fri, 13 Jun 2014 11:57:12 -0400

People in Tajikistan are very welcoming. The author and his travel companions were invited for tea and a meal at the home of their cab driver. Credit: Ondrej Kozel.

Exploring Tajikistan, and especially the Pamirs, is not for everybody, but if you’re up for an off-the-beaten-path adventure with some of the nicest people in the world, I highly encourage a visit. It’s not easy to get there; from the U.S., most flights go through Istanbul, Turkey. Once you arrive in Tajikistan’s capital, Dushanbe, you can either take a single-engine plane to Khorog or a shared van. Beware that flights to Khorog are canceled routinely due to inclement weather. Shared vans leave every day during the summer months from Dushanbe to Khorog. The typical price is 300 somoni, or about $60, one way, not bad for a 12-hour-plus drive. Getting around Khorog and the rest of the Pamirs is also best done by taxi or shared van.

Travels in Geology: Trekking the high terrain of Tajikistan

Fri, 13 Jun 2014 11:32:25 -0400

Credit: Ondrej Kozel

The author (center) and his Czech hiking companions (Vaclav Herda, left, and Vaclav Mulac, right) at the entrance to Tajik National Park. Credit: Ondrej Kozel.

There are moments in life when you need to catch some fresh air. For me, finishing my master’s degree and figuring out what to do next was such a moment. So, I set out to explore a land half a world away that I’d recently become familiar with, courtesy of a geotechnical engineering report about the world’s largest natural dam. Luckily, I speak Persian and am accustomed to backpacking in remote, high-altitude locations, so I was as prepared as I could be to travel to the backcountry of Tajikistan.

Geomedia: Books: A changing literary climate

Mon, 09 Jun 2014 13:16:26 -0400

Cli-fi is a new genre. Credit: Callan Bentley.

The book cover of “Odds Against Tomorrow” (2013) by Nathaniel Rich features a flooded Manhattan. In a 2013 NPR story, Rich’s publicist, Brian Gittis, recounted how he left his waterlogged New York City office during Hurricane Sandy and came home to sort through advance copies of books, coming across Rich’s timely cover. Gittis called it a “Twilight Zone moment.”

Southeastern caves shuttered to slow the spread of bat-killing disease

Thu, 05 Jun 2014 22:27:07 -0400

Little brown bat with White Nose Syndrome. Credit: Moriarty Marvin, U.S. Fish and Wildlife Service.

Since White Nose Syndrome was first identified in dead bats recovered from a cave in New York state in 2006, the mysterious fungal disease has wiped out more than 5 million bats in the eastern U.S., and efforts to halt its southern and western spread have become increasingly desperate.

Getting there and getting around Croatia

Fri, 16 May 2014 11:26:23 -0400

Although there are no direct flights between the U.S. and Croatia, the capital, Zagreb, is connected year-round to most major European cities, and the Dalmatian Coast airports of Split and Dubrovnik are well connected during the summer. All three offer numerous car rental options; an online consolidator such as Auto Europe can help you efficiently find the best price. One-way rentals are generally only available to other locations in Croatia and Slovenia.

Travels in Geology: Croatia: Land of limestone

Fri, 16 May 2014 10:56:02 -0400

Lying at the crossroads of Southern Europe and the Mediterranean, the Republic of Croatia could be called a “land of limestone.” Whether you choose to circumnavigate the fortified walls of one of Europe’s best-preserved medieval cities, lounge on a white cobble beach by the azure Adriatic Sea, or hike past aquamarine pools and countless waterfalls in the country’s largest national park, Croatia’s nearly ubiquitous limestone bedrock produces a majestic and unforgettable landscape.

New burgess shale fossil site found in Canada's Kootenay National Park

Fri, 16 May 2014 09:55:32 -0400

With its plethora of ancient and exquisitely preserved soft-bodied fossils, the Burgess Shale in Canada’s Yoho National Park is one of the world’s most famous fossil sites. Now a sister site has been discovered just 40 kilometers away in Kootenay National Park, and the new find may prove even richer than the original.

Geomedia: Books: Science in fiction

Thu, 15 May 2014 12:21:35 -0400

As a science magazine, EARTH usually reviews nonfiction. This month, however, we are bringing you reviews of three recent novels with scientific themes that might make nice additions to your summer reading list. The three novels fall neatly into classic genres — the murder mystery, the high-stakes thriller and the science-infused fantasy — so hopefully there is a little something for everyone. Warning: spoilers follow.

Subarctic lakes belch more methane on brighter days

Thu, 15 May 2014 10:14:36 -0400

An aerial view of some of the subarctic lakes in Sweden studied by Martin Wik and his team. Credit: Jo Uhlbäck

Each summer, frozen ground in Arctic and subarctic regions, called permafrost, thaws and releases accumulated methane. For years, scientists have searched for a clear-cut way to estimate the amount of this potent greenhouse gas that these areas contribute to the atmosphere and the changing climate. Now, they have come one step closer to solving part of the problem.

Recovery of 1960s sea-ice satellite images wins dark data contest

Wed, 14 May 2014 11:19:49 -0400

Visualization of 2010 Arctic sea ice maximum. Credit: NASA.

As part of the Nimbus Data Rescue Project, the NSIDC/NASA team processed and digitized data and images from NASA’s early Nimbus satellites. The earliest images were collected by Nimbus 1 in 1964 as it circled Earth in August and September — the time of year when sea ice reaches its annual minimum and maximum extent in the Arctic and Antarctic, respectively — equipped with little more than a camera. That camera transmitted still photographs of Earth’s surface back to scientists, who filmed the images as they appeared on a TV screen. After being archived for decades, the team was able to scan tens of thousands of photographs, originally used for weather research, and stitch them together with modern software to produce maps of the sea-ice extent surrounding both poles. Resurrection of the Nimbus data thus extended the satellite record of sea-ice extent, which had previously only dated back to 1979, an additional 15 years.

Staking a claim: Deep-sea mining nears fruition

Wed, 14 May 2014 10:51:02 -0400

Credit: Kathleen Cantner, AGI.

In the late 1970s, geologists in a deep-sea submersible several kilometers below the waves on the Galapagos Rift discovered a previously unknown world: hydrothermal vent systems supporting an array of exotic life that thrived in the absence of sunlight, subsisting instead on metals and minerals leached from the seafloor. Such hydrothermal vent systems are now recognized features of mid-ocean ridges.

Mix of acid mine drainage and fracking fluid a recipe for remediation?

Wed, 14 May 2014 10:40:43 -0400

In the Appalachian Basin, “there are hundreds of points where acid mine drainage is discharged to streams. … It’s a nuisance that affects the environment,” says Avner Vengosh, a geochemist at Duke University and a co-author of the new study, published in Environmental Science & Technology. Similarly, flowback water from shale gas operations is bad news if it’s discharged into the environment without being adequately treated, he says, because, after being injected deep underground, it returns to the surface loaded with radium, barium, strontium and other dissolved elements, which can accumulate in stream sediments.

Humans causing California's mountains to grow

Wed, 14 May 2014 09:56:28 -0400

A study of more than 500 GPS stations in Southern California and Nevada found an anthropogenic signal in uplift of the Sierra Nevada and the California Coast Ranges related to long-term water withdrawal from aquifers in the San Joaquin Valley. Credit: UNAVCO

Humankind has proven time and again that it can reshape mountains, or even tear them down. Now, it appears, we can make them rise as well. Geologists studying growth rates of the Sierra Nevada and of central California’s Coast Ranges have identified an anthropogenic contribution to the mountains’ uplift that they suggest is tied to the decades-long depletion of groundwater in the state’s Central Valley. What’s more, the researchers report in a study published today in Nature, the long-term water loss may be affecting how stress builds up on faults like the San Andreas.

Reading the walls

Tue, 13 May 2014 13:52:11 -0400

What distinguishes a New England stone wall from a pile of stones? Noted stone wall expert Robert M. Thorson, a geologist at the University of Connecticut, considers a stone wall to be “any continuous row of large stones or stack of smaller ones that is more than four times as long as it is wide.” Anything shorter, he says, “is a cluster or pile of stones, not a wall.”

The history, science and poetry of New England's stone walls

Tue, 13 May 2014 11:24:52 -0400

In 2007, I returned to eastern Connecticut, where I grew up. Driving north on Interstate 395 past towns like Norwich and Griswold, I was struck by the many old gray stone walls tumbling off into the forests along the highway. Realizing that the trees in those forests weren’t particularly old, I surmised that those forests had once been cleared farm lands.

Geologic Column: Riding the rails to Omaha with Rudolf Clausius

Mon, 12 May 2014 13:50:21 -0400

Credit: Ammodramus, public domain.

If someone points out to you that your pet theory of the universe is in disagreement with Maxwell’s equations — then so much the worse for Maxwell’s equations. … But if your theory is found to be against the Second Law of Thermodynamics, I can give you no hope; there is nothing to do but to collapse in deepest humiliation. – Sir Arthur S. Eddington

Benchmarks: May 6, 1852: Edward Sabine links the geomagnetic and sunspot cycles

Mon, 12 May 2014 12:36:59 -0400

Geophysicist and astronomer Edward Sabine (1788–1883). Credit: Bibliothèque Nationale de France, public domain

At the beginning of the 19th century, little was understood about Earth’s magnetic field, but interest in its workings had begun to grow, especially in Europe. That the magnetic field exists had long been recognized, and magnetic compasses had aided in navigation for centuries, particularly at sea where fixed landmarks are hard to come by. Not surprisingly, the increased attention emerging around the turn of the century came from naval and shipping interests, which recognized that an accurate understanding of the field’s behavior would be a boon to their fleets.

Beyond rocks for jocks: Elevating geoscience education

Fri, 25 Apr 2014 12:54:41 -0400

Credit: Copyright Shutterstock.com/Goodluz

When I was an undergraduate student, all liberal arts students were required to take a science course as a general education requirement. If I recall correctly, the science options were astronomy, biology, chemistry, physical geology and physics. The astronomy, chemistry and physics classes were highly quantitative, which frightened off many general education students. The alternatives of biology and physical geology tended to be more attractive because their core content was less rooted in high-level mathematics. Thus, the physical geology course was a favorite of athletes seeking to fulfill a general education requirement, and for this reason it was called, as it is at many schools, “Rocks for Jocks.”

Getting there and getting around in New Zealand

Thu, 24 Apr 2014 13:58:36 -0400

Auckland, on the North Island, has the country’s largest airport and is the primary international arrival point. The South Island’s largest airports are at Christchurch and Queenstown, but neither hosts direct flights from the U.S.

Travels in Geology: From beaches to bush: Tramping in New Zealand

Thu, 24 Apr 2014 13:30:21 -0400

Credit: Kathleen Cantner, AGI

With its stunningly beautiful landscapes, adrenaline-boosting attractions, renowned wines and craft beers, and easy logistics, New Zealand is one of the world’s foremost tourist destinations. It is especially well known for superb hiking, locally referred to as “tramping” or “bushwalking.” From short strolls through lush temperate rainforest to challenging alpine tracks, New Zealand offers a lifetime’s worth of outstanding walks.

Geomedia: California's climatic catastrophes detailed in "The West Without Water"

Wed, 23 Apr 2014 14:45:55 -0400

On a drought map of California for this past winter, the colors graded from yellow to deep red, indicating drought ranging from abnormally dry to exceptionally dry. The rest of the West is also dry, but the drought epicenter is California, where in January the governor declared an emergency and called for water use reductions to delay the nearly inevitable rationing to come.

Naturally occurring methane found in groundwater in New York

Wed, 23 Apr 2014 14:25:10 -0400

In 2008, when dangerously high levels of methane were found in drinking water wells in Dimock, Pa., fingers were pointed at nearby hydraulic fracturing operations as the source of the contamination. Six years later, the debate still rages over whether the town’s methane problem was exacerbated by drilling operations or if it was there all along. Now a new study is adding some much-needed baseline data for methane levels in groundwater in the natural gas-rich Marcellus Shale region of New York. The results suggest that, in some cases, methane occurs at naturally high levels in groundwater, without the influence of gas exploration and production.

Observing a plate boundary

Wed, 23 Apr 2014 07:48:13 -0400

Credit: UNAVCO

More than 280 continuous GPS (cGPS) stations in Cascadia are part of the U.S. Plate Boundary Observatory (PBO), a component of EarthScope, which includes more than a thousand cGPS stations arrayed across the western United States and Alaska. Operated by UNAVCO, PBO provides continuous data to researchers studying tectonics and earthquakes. Each PBO station operates autonomously to record and transmit up to one sample per second. In addition to PBO, the U.S., New Zealand, Japan and Canada have implemented similar networks of cGPS stations with the intent of capturing both slow and rapid motion. By combining simultaneous data from multiple receivers, scientists can use cGPS networks to produce positioning and ground motion data with millimeter precision. Data from continuous stations can be blended with campaign studies, many of which share a fleet of GPS receivers managed by UNAVCO, to provide an effective tool for seismic research.

A truly global system

Wed, 23 Apr 2014 07:43:02 -0400

Credit: Kathleen Cantner, AGI

Like the GPS navigation system in your car or smartphone, a high-precision GPS receiver uses signals from satellites to determine the distance from the receiver to the satellite. But that’s where the similarities end. Today’s scientific and commercial-grade GPS receivers use two frequencies and carrier phase measurements (distance expressed in units of cycles of the carrier frequency) to produce precise results. In addition to the U.S. GPS satellites, many receivers use data from Russia’s GLONASS navigation satellites and are capable of using signals from the planned European (Galileo) and Chinese (BeiDou) systems. New U.S. satellites will provide an additional third frequency. The combination of the new and existing satellites is collectively known as the Global Navigation Satellite System, or GNSS. GNSS will provide significant benefits to commercial applications such as surveying, agriculture and construction, as well as earth science research.

A new tool for atmospheric studies

Wed, 23 Apr 2014 07:31:18 -0400

Scientists are putting GPS to work in some unexpected new ways. For example, John Braun, a project scientist at the University Corporation for Atmospheric Research (UCAR) in Boulder, Colo., is using GPS to measure precipitable water vapor.

Mapping how malaria risk changes as new dams go up

Thu, 17 Apr 2014 15:07:58 -0400

Malaria is considered a leading public health problem in Ethiopia, with almost 70 percent of the country’s total population of more than 90 million people at risk from the deadly disease. Now, researchers are studying how hydroelectric dams affect malaria prevalence by combining computer simulations with field data from the Ethiopian countryside. The hope is that the new research could provide fresh insight for malarial management programs.

Scientists look wider and deeper to predict the next El Nino

Tue, 15 Apr 2014 20:05:49 -0400

The reds in this band show the general areas of sea-surface temperatures that affect the formation of an ENSO event. Anomalously warm temperatures in the equatorial Pacific tend to indicate an El Nino event; anomalously cool sea-surface temperatures in that region tend to indicate a La Nina event. Credit: NOAA.

Whether it be the two monsoons that wiped out Kublai Kahn’s conquest of Japan, or the fog in Long Island that allowed George Washington and his troops to escape with their lives, the predictability of the weather (or lack thereof) has left its mark on human civilization. Of all climate and weather phenomena, the El Niño Southern Oscillation (ENSO) is one of the most well known for its impact on world climate and human life, but is also one of the most puzzling to scientists. Recently, researchers have begun accounting for a much more global dataset than previously considered in the hopes of predicting El Niño or La Niña conditions sooner than is currently possible.

Precise to a fault: How GPS revolutionized seismic research

Mon, 14 Apr 2014 12:57:55 -0400

The Global Positioning System is a constellation of more than 30 satellites orbiting Earth twice a day at an altitude of more than 20,000 kilometers. Geoscientists use GPS to make precise measurements of position and ground motion. Credit: Kathleen Cantner, AGI

In the late 1980s, Ken Hudnut, a Columbia University graduate student studying plate tectonics in Southern California, began experimenting with a new technology, called the Global Positioning System (GPS), as a way to measure the slow, relentless motion of Earth’s crustal plates.

Fieldwork revises ice-free corridor hypothesis of human migration

Tue, 08 Apr 2014 19:26:45 -0400

Researchers sample a boulder known as a glacial erratic to determine when it was deposited. Credit: Lionel Jackson.

The existence of an ice-free corridor through Canada during the climax of last glaciation, which allowed the first Americans to cross the Bering land bridge from Siberia and move south (about 13,000 years ago), has long been postulated in North American archaeology. Now, research based on the exposure ages of glacial rocks found in the corridor suggests a puzzling conclusion — that the open pathway closed several thousand years prior to 20,000 years ago and didn’t open again until between 13,000 and 12,000 years ago, well after the first Americans were in the Americas.

Resolving a misplaced source of volcanism in the Galapagos

Mon, 07 Apr 2014 14:04:56 -0400

A view of an active volcano on Isabela Island in the Galapagos. Credit: Doug Toomey.

Geological models have long suggested the mantle plume that built the Galápagos islands lies below Fernandina Island. Using a novel combination of seismic techniques, however, scientists have found a mantle anomaly that appears to be the Galápagos plume located 150 kilometers southeast of Fernandina Island. The new findings better explain the ongoing volcanic activity and also shed light on interactions between the mantle and crust, researchers say.

Social sciences improve tornado warnings

Wed, 02 Apr 2014 14:36:02 -0400

A tornado strikes near Osceola, Neb., in 2011. Credit: Greg Dumas/NOAA.

In 2013, 55 people in seven states were killed by tornadoes. Now, scientists behind a new report analyzing the effectiveness of tornado-warning processes are hoping to help reduce tornado fatalities in the 2014 storm season by combining the latest storm-tracking technology with a better understanding of how communities and people respond to tornado warnings.

The Chesapeake Bay gets some good news

Wed, 19 Mar 2014 10:35:38 -0400

The Susquehanna River in eastern Pennsylvania is one of 150 major rivers that eventually flow into the Chesapeake Bay, transporting pollutants and nutrient runoff from six states. Credit: Mary Caperton Morton

By Mary Caperton Morton

Volcanic lightning generated in a bottle

Wed, 19 Mar 2014 10:10:31 -0400

Lightning was captured in images of the erupting Sakurajima Volcano in southern Japan in January 2013. Credit: Copyright Martin Rietze.

In A.D. 79, during the catastrophic eruption of Mount Vesuvius, Pliny the Younger wrote of a “blaze of lightning” illuminating the ash plume, marking the first recorded observation of volcanic lightning. Nearly 2,000 years later, scientists still know very little about how lightning is generated by volcanic eruptions, in large part because of the danger and difficulty in monitoring the phenomenon in the field. But a new apparatus for generating volcanic lightning in the lab may shed light on the subject.

Geologic Column: Data security: freezers, floppies and flash drives

Fri, 14 Mar 2014 14:28:32 -0400

How do you back up your precious data?Credit: ©Shutterstock.com/Sergey Nivens.

In the pre-electronics-dominated world, many of us protected our field notes, lab records and draft manuscripts by making multiple photocopies, storing them in different places, and perhaps keeping one in the freezer in case of fire. Today, much of our data is collected and stored electronically, and we use different strategies to protect against catastrophic loss. Full sessions on data storage and data recovery at last fall’s Geological Society of America and American Geophysical Union meetings got me thinking about storage. So I asked an assortment of colleagues about their strategies for protecting their data — both earlier in their careers and today.

Scientists go to extremes to monitor Arctic permafrost loss

Fri, 14 Mar 2014 11:00:55 -0400

USGS scientist Frank Urban peers over the edge of an overhanging bluff. The grassy mat of surface vegetation often remains intact the longest and hangs off the edge of the undercut icy sediments. Credit: Adam LeWinter, Extreme Ice Survey.

In late summer 2008, the phone rang in my office at the Institute of Arctic and Alpine Research in Boulder, Colo. On the other end of the line was my colleague Frank Urban, a U.S. Geological Survey (USGS) climate scientist, who was calling, via satellite phone, from our research site in Alaska on the shore of the Arctic Ocean.

IPCC: A failure in communicating the impact of new findings

Mon, 10 Mar 2014 13:01:30 -0400

In October, the Intergovernmental Panel on Climate Change (IPCC) released its Summary for Policymakers (SPM) to accompany the report of Working Group I on the physical science evidence for a warming planet. The SPM is designed to be the headline-grabbing addendum to the main report, written in plain language for nonscientists: policymakers, the media and the public. It is supposed to explain the findings of the unwieldy main report in a clear, concise manner. It fails to do so. I found it disappointing — not so much because of the science, but because of the way it presented the science. The report was written by top scientists involved in putting together the main report, so what went wrong?

Sudden gas eruption shakes the ground near Rome's airport

Mon, 03 Mar 2014 18:36:13 -0500

Gas leaks from the crater found near Rome's airport. Credit: Giancarlo Ciotoli.

On Aug. 24, 2013, visitors arriving at Rome’s Leonardo da Vinci International Airport, located in the Fiumicino municipality, flew over a surprising hazard: a gas emission that suddenly exploded from the ground a few meters outside the airport compound. The expulsion, referred to as the Fiumicino Gas Vent (FGV), occurred about 15 kilometers southwest of Rome and was first noticed by passing motorists. Shortly after the explosion, scientists sought to determine the gas’ makeup and whether it posed a continuing danger.

From boom to bust in Neolithic Europe

Thu, 20 Feb 2014 10:11:20 -0500

Even after the introduction of agriculture to Europe about 8,500 years ago, growing Neolithic communities still experienced large population swings. Copyright Mary Harrsch, Creative Commons Attribution-NonCommercial-ShareAlike 2.0 Generic

As agricultural practices spread from the Fertile Crescent across Europe, gradually expanding west and north starting about 8,500 years ago, they brought increased and localized food production to a continent where nomadic hunter-gatherers had long made their living subject to the whims of climate and the environment. With agriculture, long-term settlements developed, fertility rates rose and, thus, populations grew steadily. Or at least that’s been the conventional wisdom.

From field scientist to filmmaker: Doug Prose

Thu, 20 Feb 2014 09:58:57 -0500

Geo-documentarian and filmmaker Doug Prose. Diane LaMacchia

With a background in writing and film production, Diane LaMacchia — Prose's co-producer and wife — writes, directs and edits films at Earth Images Foundation. Doug Prose

Whether it has been filming from precarious positions (like this one overlooking a volcanic crater in Ecuador) or sleeping in a self-made snow trench during Antarctic cold-weather training, Prose has had his share of brushes with danger. Diane LaMacchia

Ask Doug Prose what his favorite part of producing geologically themed documentaries is and he’ll tell you it’s filming nature and science in the field that excites him most. In particular, it’s the company of awe-inspiring landscapes, eminent experts and eager students; it’s capturing science in action, and researchers’ reactions at moments of discovery; it’s even logistical elements like composing camera shots and, when needed, managing curious onlookers crowding sometimes camera-shy scientists.

Brooks Ellwood and the unusual applications of magnetism

Thu, 20 Feb 2014 09:26:45 -0500

Comparing a historical photo of a cemetery in Giddings, Texas, to modern-day photos and removing modern additions like phone lines and curbing, Brooks Ellwood and his team noticed three trees and five monuments common in both photos, allowing them to locate the possible position of Wild Bill Longley's grave. Sure Ellwood

Ellwood, Smithsonian forensic anthropologist Doug Owsley and their team then excavated where the computer work indicated, and found the long-lost gravesite of Wild Bill. Sure Ellwood

Ellwood pioneered the use of the MagnetoSusceptibility Event and Cyclostratigraphy (MSEC) technique to study Global Boundary Stratotype Section and Point (GSSP) localities around the world, such as this one near Luxor, Egypt. Brooks Ellwood

The call came out of the blue. Geophysicist Brooks Ellwood was sitting in his office in the geology department at the University of Texas at Arlington in 1990 when the telephone rang. On the other end was Doug Owsley, a forensic anthropologist at the Smithsonian Institution, who was calling to ask for Ellwood’s help to find the grave of “Wild Bill” Longley. Little did Ellwood realize that this seemingly straightforward request would set him off on a 10-year quest.

Geoscience inspires glass artist Adam Frus

Thu, 20 Feb 2014 09:08:56 -0500

Adam Frus has been blowing glass since he was 16. He creates art inspired by the geosciences in color, content and style. Courtesy of Adam Frus

Artwork was a staple in Adam Frus’ boyhood home in Jacksonville, Fla. “Growing up, my parents took me to a lot of art shows, which taught me the value of creating something beautiful,” he says. But his true love for art took off when, at the age of 16, he took a glass-blowing class with his father and brother. Frus has now been working in blown glass for the better part of two decades, and in 2007, he started his own company, Frus Glass. He wasn’t always sure he wanted to be a professional artist, however, and he first pursued geology, graduating with a degree in geology from Arizona State University in 2007. Now he uses that geological background and love of the earth sciences to inform his art.

Getting there and getting around on the John Muir Trail

Tue, 18 Feb 2014 09:56:09 -0500

Getting to the trail can be a challenge, but one way is the Yosemite Area Regional Transportation System bus, seen here at the Merced train station. Copyright Ricky Courtney, Creative Commons Attribution-ShareAlike 3.0

The best time to hike the John Muir Trail (JMT) is late summer. To plan your own adventure, start by reading up on the trek at various websites such as the Pacific Crest Trail Association’s JMT trail site (www.pcta.org/discover-the-trail/john-muir-trail/) and in guidebooks. Then, when you know when you want to go, procure your permits. To start in Yosemite, you can apply for permits through their lottery over the winter or get a permit for an alternate trailhead like we did. Or, if you have enough time to be flexible, you can try to get some of the first-come, first-served permits available every day. Most people do the 340-kilometer trip in two to four weeks, depending on their hiking pace and interest in exploring side trips or taking days off.

Be aware and prepare

Tue, 18 Feb 2014 09:53:03 -0500

Hiking the full 340-kilometer length of the John Muir Trail (JMT) isn’t a beginner backpacking trip. Make sure you enjoy slowly plodding up switchbacks carrying a heavy pack for days before you start out on this weeks-long trek. That said, I met a surprising number of people for whom the JMT was their first wilderness foray, and as far as I know, they all survived.

Travels in Geology: Walking toward Whitney: A journey through the Sierra High Country along the John Muir Trail

Tue, 18 Feb 2014 09:26:19 -0500

From atop Mount Whitney — the tallest peak in the lower 48 states — ridge upon ridge of Central California’s Sierra Nevada range stretches out before you, the topography blurring into the northern horizon. My travel companion and I arrived at Mount Whitney’s peak after a 340-kilometer hike through the High Sierras along the John Muir Trail (JMT) — climbing up and down many of the ridges that now fade in the distance. Having just traversed the trail, one boot-step at a time, you can appreciate the scale of the scenery all the more: You’ll understand just how high you truly are and that those ridges, their severity now softened by distance, are anything but tame.

Harvesting fog could bring water to millions

Mon, 13 Jan 2014 13:17:37 -0500

Fog collectors resemble volleyball nets with tighter weaves. Standard fog collectors are getting a boost with an optimized stainless steel mesh, as shown here near Pena Blanca, Chile. Water is collected in the white plastic drum. K.C. Park

In northern Chile, as in many other parts of the world, freshwater is a limited commodity, but heavy fogs are a regular occurrence. For at least two decades, people in such areas have turned to fine mesh nets to harvest moisture from fog, but to date the nets have never been terribly efficient. Now, new research could greatly improve the nets’ efficiency, increasing the amount of water they’re able to capture.

Hazards abroad: Sent home

Tue, 10 Dec 2013 10:08:22 -0500

On May 19, 2012, seismologist Roger Bilham of the University of Colorado at Boulder landed at the airport in Delhi, India, on his way to Bhutan. He debarked from the plane and was met by Indian customs officials, who declared he was on the “blacklist” and not allowed entry to India, despite having a valid visa. Two hours later, he was on a plane heading back to the U.S.

Geologic Column: Beer's secret ingredient: geology

Wed, 20 Nov 2013 11:55:19 -0500

Geologists have a long history with beer. Earlier this year, I decided to raise my own beer appreciation to the next level and take a class on the subject. I attended the beer school at the Anheuser-Busch Brewery in St. Louis. A few minutes into the class, our instructor noted that the beer-brewing process uses clean water, which, he said, is basically the same no matter where you are. Unfortunately, that got us off on the wrong foot. As anyone in the beer business should know, water — and what’s in the water, courtesy of the geology through which it percolates — can make all the difference in an end product.

Blogging on EARTH: A letter from field camp

Wed, 24 Jul 2013 18:30:37 -0400

Bryce Mitsunaga at field camp in Montana. Bryce Mitsunaga

The 2013 University of Houston-YBRA field camp participants exploring glacial features atop the Beartooth Range. Bryce Mitsunaga

University of Houston-YBRA field camp, summer 2013. Bryce Mitsunaga

Learning the basics of mapping includes how to take a strike and dip. Bryce Mitsunaga

Bryce Mitsunaga, a recent graduate of Williams College in Williamstown, Mass., is currently attending field camp at the Yellowstone-Bighorn Research Association camp located in the Beartooth Mountain Range outside of Red Lodge, Mont. In honor of EARTH's August feature on field camps, Bryce wrote in with some reflections on his experiences so far.

Location, Location, Location

Fri, 19 Jul 2013 09:33:39 -0400

Although field camps based east of the Mississippi River do exist, and a handful of American schools run camps abroad in places like Ireland, Italy and parts of Africa, the vast majority of camps in the U.S. are still conducted out West. From the Black Hills and the Great Plains, across the Rockies and other mountain ranges, to the Desert Southwest, the western U.S. offers much in the way of beautifully exposed outcrops, distinctive landscapes and transects through long stretches of geologic time.
Naturally, every field camp director is partial to the plots of land to which he or she returns each year. Here’s what a few of them had to say about their particular field sites.

Bare Earth Elements: The field camp experience in photos

Tue, 16 Jul 2013 17:08:15 -0400

For the August issue of EARTH, I wrote about some of the ways in which geology's longstanding rite of passage — field camp — has changed over the years, as well as how it has remained the same. In the process of researching and reporting the story, I had the great pleasure to speak with past and present field camp directors (a couple of whom I knew already from my own time as a graduate student) about the camps they oversee and about their experiences both attending and leading field camps. I also collected many more photographs than we could run with the story, so I thought I'd put together a slideshow to showcase a few more. Enjoy!

Blogging on EARTH: Spring has sprung, at least in some places

Fri, 19 Apr 2013 13:21:01 -0400

Looking out the window somewhere between Greenland and Baffin Island on a flight in April from Amsterdam to Portland. Julia Rosen

More snow fell on Minneapolis on April 18.Ehren Rudolph

Spring was nowhere to be found during my recent three weeks of travel through Europe; not in the olive orchards of southern Italy, the cobbled streets of Copenhagen, or the banks of the Danube as it winds through central Vienna. Instead, winter has dragged on stubbornly — the worst in 43 years — leaving behind relict patches of snow in shadowy alleys and warning new leaves not to adorn the bare branches of trees with vernal green. I hear from (understandably cranky) friends across North America that winter is hanging on here too, with more snow falling this week in Colorado, Minnesota and in between.

Blogging On Earth: Humans acidifying ocean at unprecedented rate

Thu, 01 Mar 2012 06:08:23 -0500

Human emissions of carbon dioxide are currently acidifying the oceans at a rate unprecedented in the last 300 million years — since well before the dinosaurs evolved — according to a study published today in Science. More acidic water can dissolve the shells of many marine organisms, including reef- and shell-building species, such as clams, oysters and corals, as well tiny organisms that form the base of the food chain.

A tale of two rocks: Moon-like rocks right next door

Thu, 05 Jan 2012 06:41:58 -0500

An Apollo 16 astronaut drills in simulated lunar soil during a training exercise before a moon landing. NASA Kennedy Space Center

Apollo astronauts brought lunar rocks and soil back to Earth for analysis. Johnson Space Center

The Luck Stone Corporation of Virginia supplied NASA scientists with diabase samples for their work. Luck Stone Corporation

Photomicrograph of a thin section of lunar basalt under cross-polarized light. The basalt was collected by Apollo 17 astronauts. Kurt Hollecher, Union College

Researchers from NASA and Honeybee Robotics filled a 10-meter-tall pipe with crushed diabase from Virginia to simulate drilling on the moon. It worked. Courtesy of Kris Zacny and Patrick Fink, Honeybee Robotics

The Lunar Roving Vehicle was designed to transport astronauts and materials on the moon during the Apollo 15 (shown here), Apollo 16 and Apollo 17 missions in 1971 and 1972. NASA Marshall Space Flight Center

NASA's K-10 rover has been tested at Haughton Crater in northern Canada and other locations to see if it's suitable for lunar travel. At the front of the rover is a geotechnical tool that assesses soil strength. Courtesy of Kris Zacny and Patrick Fink, Honeybee Robotics

Lunar exploration is once again in full swing. Japan’s Kaguya and India’s Chandrayaan-1 satellites are currently in orbit around the moon. China’s Chang’e spacecraft, after a successful mission, has been intentionally crashed on the moon. And the United States’ Lunar Reconnaissance Orbiter is preparing to launch. These are all unmanned missions; humans haven’t been to the moon in more than 30 years. But we will probably return in the next decade, and when we do, we hope to dig even deeper to uncover the moon’s secrets.

Afghanistan's mineral wealth

Thu, 05 Jan 2012 06:41:58 -0500

Blogging on EARTH

On Monday, a spokesman for Afghanistan's President Hamid Karzai, Waheed Omar, told reporters that the USGS survey of Afghanistan's mineral resources found they are worth about $1 trillion. And on Wednesday, USGS will host a press conference in which scientists will discuss water issues in Afghanistan.

AGU: Mount St. Helens has gone back to sleep

Thu, 05 Jan 2012 06:41:58 -0500

Aerial view of Mount St. Helens' crater, as seen from the north on May 30, 2008. Scientists say the eruption that has been ongoing since October 2004 ended early this year. Steve Schilling, USGS

Seismometers recorded a spike in earthquake activity when the volcano first renewed its eruption in October 2004. Seismic activity has since waned. John Clemens, USGS

USGS scientist Michael Poland collects information from a GPS station on the east flank of Mount St. Helens. Many GPS stations have been installed on or around the volcano to measure ground deformation. Dan Dzurisin, USGS

Researchers dropped "spiders" onto Mount St. Helens' growing lava dome to track the eruption in locations too dangerous for humans to go. Dan Dzurisin, USGS

One way researchers gather data on volcanic gas emissions is through devices like this on the helicopter step, which collects data as researchers fly over the volcano. Ken McGee, USGS

The decapitated Mount St. Helens in 1983, three years after the devastating 1980 eruption that killed 57 people. The gigantic debris avalanche that removed the former summit swept through Spirit Lake, spawning a 250-meter tsunami. USGS Cascades Volcano Observatory

SAN FRANCISCO — After more than three and a half years of continuous eruption, Mount St. Helens in Washington quieted earlier this year. Following intense monitoring efforts, the volcano is officially “asleep,” researchers reported Thursday at the annual meeting of the American Geophysical Union.

Alaska's Mt. Redoubt erupts at last

Thu, 05 Jan 2012 06:41:58 -0500

Blogging on EARTH

After months of threatening and rumbling, Mount Redoubt finally erupted late Sunday night.

Redoubt began to exhibit increasing unrest last fall, with seismic activity becoming markedly increased in January, and expectations of an imminent eruption were growing. On March 15, researchers detected four hours of continuous volcanic tremor and observed of a brief plume of gas and ash, according to the U.S. Geological Survey's Alaska Volcano Observatory.

Ancient meteorites reveal early magnetic fields

Thu, 05 Jan 2012 06:41:58 -0500

New research suggests that some of the small rocky bodies that smashed together to form planets, called planetesimals, had magnetic fields. Damir Gamulin, courtesy of Benjamin Weiss

Even before the birth of the planets, our solar system was hardly a lonely place. Small rocky bodies, called planetesimals, filled the inner solar system, eventually colliding together to form the planets. Now a new look at a group of ancient meteorites shows that at least some planetesimals generated their own magnetic fields — a feat many scientists thought extremely difficult for such small astronomical bodies. The work also has scientists rethinking how planets formed.

Bacteria back from the brink

Thu, 05 Jan 2012 06:41:58 -0500

Layered salt crystals, colored pink and green from trapped microorganisms. From a layered salt pan in Saline Valley, Calif. Michael Timofeeff

A microbial bloom of living, green _Dunaliella _algae found within a fluid inclusion in a salt crystal. Michael Timofeeff

Thousand- and million-year-old microbes found living in salt crystals: Could they also exist on other planets?

Blogging on EARTH: South Sudan secedes - what does that mean for its oil?

Thu, 05 Jan 2012 06:41:58 -0500

Today, South Sudan is voting on whether to secede from North Sudan. Although all votes have not been counted, signs point to the South becoming its own country. But given that South Sudan holds more than 70 percent of Sudan’s 5 billion to 6 billion barrels of proven oil reserves, a lot in this election hinges on oil, as EARTH explores in its February feature.

Chemical clues reveal ancient geography

Thu, 05 Jan 2012 06:41:58 -0500

Reconstructing the history of supercontinents requires careful detective work. A variety of geological processes wipes the evidence clean, like a burglar who smears away his fingerprints. Yet even the most cautious criminals leave clues behind — and so do supercontinents.

Comet finished off North American big game animals, cooled the planet?

Thu, 05 Jan 2012 06:41:58 -0500

Fires from a comet shower may have killed off the big game in North America about 13,000 years ago, scientists say. Those extinctions have long been attributed either to an abrupt return to glaciation known as the Younger Dryas event or to over-hunting. But now, a team of scientists has found tiny, nanoparticle-sized diamonds in sediments from the Younger Dryas — signs that a cosmic impact may have ultimately been behind both the cold period and the extinctions.

Creeping faults warn of impending earthquakes?

Thu, 05 Jan 2012 06:41:58 -0500

San Andreas Fault U.S. Geological Survey (USGS): photographer Robert E. Wallace, USGS.

Researchers drilled the San Andreas Fault and extracted core samples that are now being studied. John I. Garver, National Science Foundation

Studying the San Andreas Fault, Fenglin Niu and colleagues recently found a way to help determine that an earthquake is coming. Fenglin Niu

Earthquakes strike out of nowhere — one minute everything is perfectly calm, and the next minute, the ground shakes violently and buildings crumple. However, many seemingly sudden seismic events are actually preceded by a multitude of creeping changes underground. Detecting and interpreting these changes would help forecast earthquakes, but that detection has proven difficult, partly because scientists don’t yet fully understand the complex chain of events that precipitates a quake. Now a team of researchers may have discovered some hidden clues that may help them identify impending quakes.

Criminals steal London dino's dung

Thu, 05 Jan 2012 06:41:58 -0500

It took a big dinosaur to make dung this large. This coprolite was likely from a _Maiasaura_, an herbivorous dinosaur that walked upright on its hind legs. Karen Chin

Blogging on EARTH

A series of robberies over the past five years at London’s Natural History Museum has curators frustrated — and puzzled. From stuffed squirrels to scarab beetles, it seems that anything that can be carried is vulnerable. But most oddly, some thieves made off with a piece of fossilized dinosaur dung.

D-Day's Legacy: Remnants of invasion linger in beach sands

Thu, 05 Jan 2012 06:41:58 -0500

American troops in a landing craft vehicle approach a beach in northern France on D-Day, June 6, 1944. National Archives photo no. SC320901

Before dawn on June 6, 1944, more than 160,000 Allied troops began storming the shores of Normandy, France, in what would be the turning point of World War II. Troops poured out of planes and off ships along an 80-kilometer stretch of coastline. More than 5,000 ships and 13,000 airplanes supported the ground troops. The battles were bloody and brutal, but by day’s end, the Allies had established a beachhead. Gen. Dwight D. Eisenhower said the operation was a crusade in which “we will accept nothing less than full victory.” Less than a year later, the Germans surrendered, and the Western Front of World War II came to an end.

Danger and wonder in Nat Geo's "Giant Crystal Cave"

Thu, 05 Jan 2012 06:41:58 -0500

National Geographic Channel

National Geographic Channel

Working in the Giant Crystal Cave. National Geographic Channel

National Geographic Channel

Razor-sharp rocks. Deadly crevasses. Unbearable heat. Scalding water. One false step...and you’re history.

Deciphering mass extinctions

Thu, 05 Jan 2012 06:41:58 -0500

What the planet’s past mass extinctions tell us about the future of life on Earth

The crash-landing of a 10-kilometer-wide asteroid 65 million years ago made for a very bad day for dinosaurs — or one very lucky day for mammals.

Do impacts trigger extinctions? Impact theory still controversial

Thu, 05 Jan 2012 06:41:58 -0500

AGI

The revolution started with a bang in 1980. For some, this revolution became a religion, even an orthodoxy. The true believers became proselytes and began to see signs supporting their viewpoint everywhere. But each time the proselytes claimed to have found yet another example in support of their “religion,” naysayers and doubters emerged. Two sides formed, each loudly castigating and questioning their opponents.

DOE promises $2.4 billion for clean coal

Thu, 05 Jan 2012 06:41:58 -0500

Basin Electric

Blogging on EARTH

Secretary of Energy Steven Chu announced today at a meeting of the National Coal Council that $2.4 billion in stimulus money will go to developing carbon capture and storage technologies.

Earthworms churn out calcite crystals

Thu, 05 Jan 2012 06:41:58 -0500

Any gardener can tell you that earthworms play a major role in soil ecology. But that information hasn’t always been common knowledge. Charles Darwin was one of the first to study earthworms, and in 1881, he discovered the curious fact that many species leave behind calcite crystals as they work their way through the soil. Now, new research might shed some light on the enduring mystery of how and why earthworms produce the crystals.

EIA: Worldwide oil demand will plummet in 2009

Thu, 05 Jan 2012 06:41:58 -0500

Standard Oil 'blue barrel' U.S. Department of Energy

Blogging on EARTH

The Department of Energy’s Energy Information Administration is projecting that the global demand for oil will plummet even faster next year than it did this year — largely because of lower forecasts for global economic growth.

Extinction-era coal linked to Chinese cancer epidemic

Thu, 05 Jan 2012 06:41:58 -0500

At the close of the Permian, 252 million years ago, conditions on Earth took a turn for the worse, nearly wiping out life on land and at sea in the planet’s most severe extinction event. Now, eons later, geologists are implicating a coal seam that dates to the “Great Dying” at the Permian-Triassic boundary in one of the modern world’s worst cancer epidemics.

FY 2010 budget cuts Yucca, oil and gas programs

Thu, 05 Jan 2012 06:41:58 -0500

Blogging on EARTH

The White House Office of Management and Budget released today its FY 2010 budget reductions and savings — what programs it plans to cut or reduce.

The OMB reiterates the President's focus on education, health care and alternative sources of energy in the overall budget, while slipping in some interesting cuts. Many programs were cut outright: In particular, the White House proposes to eliminate the controversial Yucca Mountain Repository Program — the Nevada site of a long-proposed national repository for high-level nuclear waste (the budget does give the Department of Energy $197 million in 2010 to look for alternative waste disposal sites).

Geology 101: Reading the story in the rocks

Thu, 05 Jan 2012 06:41:58 -0500

David Harwood’s field geology course gives future teachers an introduction to several of geology’s most fundamental principles, including the stratigraphic basics described by Nicholas Steno in 1669. Go to the head of the class with this quick primer.

Giant dunes, not mega-tsunami deposits?

Thu, 05 Jan 2012 06:41:58 -0500

Some models suggest the chevrons' orientations (black arrows) don't match the direction of arriving tsunami waves (white arrows). Robert Weiss

Tsunamis generated by asteroid impacts may have left white, sandy "chevron" deposits in Madagascar. Robert Weiss

About four years ago, a group of scientists proposed that a series of giant, wedge-shaped sandy deposits found along the shores of southern Madagascar might be evidence of a giant tsunami — a “mega-tsunami” — generated by an asteroid that may have blasted into the Indian Ocean sometime in the last 10,000 years. Furthermore, the scientists said, such impacts and the resulting tsunamis may have occurred fairly frequently during this period. To search for evidence of these impacts, the researchers formed the Holocene Impact Working Group. By 2006, with the help of Google Earth, they found dozens more of the wedge-shaped deposits, called chevrons, scattered across the planet, including in Africa, Australia and the United States.

Granite countertops: NOT silent killers

Thu, 05 Jan 2012 06:41:58 -0500

Nothing says class like a thick slab of polished granite. The stone is so durable. So chic. So modern. So...radioactive?

On Sept. 2, NBC's Today Show cautioned homeowners - especially pregnant women or families with small children - to think twice before installing granite countertops. Granite emits not only radiation, but also radioactive radon gas, explained Today Show correspondent Natalie Morales.

How amphibious whales returned to the sea

Thu, 05 Jan 2012 06:41:58 -0500

Millions of years ago, the first animals emerged from their watery habitat to live on dry land. After becoming fully adapted to a terrestrial environment, however, some animals, such as whales, ultimately returned to the ocean. But the evolutionary steps involved in that watery return have long been a mystery. Now, some exceptional fossils — and one really old baby — are shedding some light on how whales went back to the sea.

Large earthquake rocks Iran oil port

Thu, 05 Jan 2012 06:41:58 -0500

A powerful magnitude-6.0 earthquake rocked southern Iran this morning at about 3:30 p.m. local time. USGS Earthquake Hazards Program

The epicenter of the quake was about 45 kilometers west of the southern Iranian oil port Bandar Abbas. USGS Earthquake Hazards Program

The earthquake occurred near the tectonic plate boundary between the Arabian and Eurasian plates. USGS Earthquake Hazards Program

Wednesday, Sept. 10, 12:30 p.m. EDT — At 3:30 p.m. local time, a magnitude-6.0 earthquake struck Iran near the southern port city of Bandar Abbas. Tremors from the quake were felt as far away as the United Arab Emirates and Qatar, according to the U.S. Geological Survey.

Lay of the Land: Terrain's Toll on the U.S. Civil War

Thu, 05 Jan 2012 06:41:58 -0500

Nearly 23,000 men died in the Battle of Antietam, including these Confederate soldiers. Library of Congress - Alexander Gardner

In the Battle of Antietam, there were fewer casualties near Burnside Bridge, pictured here, than at the Cornfield. Ernest Mettendorf

Thousands of men died along Sunken Road, or "Bloody Lane," during the Battle of Antietam. Stephen Kellam

Antietam Library of Congress - Kurz and Allison

In the waning days of summer 1862, Gen. Robert E. Lee lined his Confederate troops along a grassy ridge on the western side of Antietam Creek in the outskirts of Sharpsburg, Md.

Mag.-8.9 quake strikes Japan, tsunami heads for Hawaii

Thu, 05 Jan 2012 06:41:58 -0500

The March 11 earthquake was preceded by a series of large foreshocks, beginning on March 9th with a magnitude-7.2 quake and continuing with a further 3 earthquakes greater than magnitude-6 on the same day. USGS Earthquake Hazards Program

A powerful magnitude-8.9 earthquake struck near the eastern coast of Honshu, Japan, today at 2:46 p.m. local time. The quake sent a tsunami racing across the Pacific Ocean to Hawaii, making landfall just before 3 a.m. local time. The Pacific Tsunami Warning Center has more information.

Mapping safer drinking water

Thu, 05 Jan 2012 06:41:58 -0500

Warmer colors represent a higher risk of arsenic-contaminated groundwater, while blues represent low-risk areas. Winkel L., Berg M., Amini M., Hug S.J., Johnson C.A., Nature Geoscience 1, 536-542 (2008)

Beginning in the 1970s, international aid agencies dug hundreds of thousands of wells in Bangladesh to help people access clean drinking water. The effort curbed diarrheal diseases, but it led to a new problem: arsenic poisoning.

Minerals also evolve

Thu, 05 Jan 2012 06:41:58 -0500

Callan Bentley

Taxonomy, the science of classification, connects creatures through genealogical relationships. But taxonomist Carl Linné (Linnaeus) didn't stop with living organisms; he applied his system to all natural objects — even minerals. And according to a new study, he may have been on to something: Iron may not pass genes to its rusted cousin iron oxide, but like living organisms, minerals have evolved considerably over the course of Earth’s history.

On Hannibal's Trail: The clues are in the geology

Thu, 05 Jan 2012 06:41:58 -0500

The Col du Clapier-Savine Coche with Turin (upper left) off in the distance. Edward Boenig, Creative Commons Attribution-ShareAlike 2.5 Generic

Standing at the summit of one of the Alps’ tallest mountain passes in the fall of 218 B.C., Hannibal peered into enemy territory: Italy’s Po River Valley. The panorama was reassuring. Hannibal’s plan — a sneak attack of the Romans on their own soil — was at last within reach. As his army trudged along a snow-covered path, Hannibal, Carthage’s greatest military leader, used the sight of Italy to encourage his ailing troops to keep going.

Raising bees and capturing rainwater: U.S. prisons go green

Thu, 05 Jan 2012 06:41:58 -0500

The flagging economy may complicate federal aspirations for a green revolution, but at least one government entity has adopted the movement in stride: state prisons.

According to a recent report by the Associated Press, prisons across America now host the likes of compost heaps, organic gardens and solar panels in an attempt to save precious state budget money.

Re-examining the Burgess Shale

Thu, 05 Jan 2012 06:41:58 -0500

Allison Daley in Walcott's original quarry in 2008. Robert Gaines

Jean-Bernard Caron at the Burgess Shale site in 2008. Robert Gaines

The Burgess Shale discovery site in the Canadian Rockies today. Robert Gaines

Jason Loxton and Michael Streng at the Burgess Shale on Mount Stephen in 2008. Robert Gaines

About 505 million years ago, the continent that would become North America straddled the equator. With no terrestrial plants or animals, the land was a barren landscape. The warm, shallow sea bordering the continent, however, hosted a carbonated reef teeming with a diverse array of organisms, most of which were relatively small bottom-dwellers. Periodically, the animals would get washed over the reef and deposited at its base, where their bodies accumulated in the muddy sediments. Today, these creatures are beautifully preserved in the Burgess Shale.

Redefining Quaternary

Thu, 05 Jan 2012 06:41:58 -0500

Blogging on EARTH

The Quaternary Period — the geologic time period that includes human evolution up to the present — is now a bit longer than it used to be.

A beloved term by many geologists, the Quaternary has long been used to refer to the two most recent epochs, the Pleistocene and the Holocene (the latter being the most recent 10,000 years). But some geologists (apparently, particularly marine stratigraphers) have considered Quaternary to be an outdated term that is part of a nearly extinct classification system for geologic time (remember the Primary and Secondary periods?) — and hoped to just fold it into the overall period "Neogene," which includes all of the last 23 million years.

Rewriting rivers: What it means for river restoration

Thu, 05 Jan 2012 06:41:58 -0500

Great Seneca Creek in Germantown, Md., looking upriver from the remnants of Black Rock Mill. The floodplain shows the typical forest-stabilized landscape that emerged after the milldam removal. Christopher M. Keane

The remnants of the milldam for Black Rock Mill on Great Seneca Creek in Germantown, Md., are only visible through residual riffle. Christopher M. Keane

A millstone commonly used in the mid-Atlantic region of the U.S. Christopher M. Keane

A meandering stream near Seneca Creek in Maryland. Christopher M. Keane

Black Rock Mill along Seneca Creek, as seen today. Christopher M. Keane

The mill race that was blasted out of the bedrock connected the millpond to Black Rock Mill itself. Christopher M. Keane

Clopper Mill, a saw- and gristmill, was erected in the early 18th century. Courtesy of Frank Ierardi

Like many rivers in the mid-Atlantic, Seneca Creek hosted numerous mills and their dams for more than a century, including Clopper Mill. Courtesy of Frank Ierardi

A milldam on the West Branch of the Little Conestoga River in Lancaster County, Pa., circa 1919. Pennsylvania Department of Environmental Protection

Dorothy Merritts surveys along a streambank in Watkin's Mill Park on Great Seneca Creek in Montgomery County, Md. Robert Walter

Mike Rahnis holds a stadia rod by a streambank on Mountain Creek in Cumberland County, Pa. Robert Walter

In 1702, Francis Chadsey and his family bought 200 hectares of meadow and upland on the banks of the Brandywine Creek in southeastern Pennsylvania. Within a year, he built a mill for grinding wheat, oats and barley. Like other landowners in the region, Chadsey also built a small dam on the creek. He most likely used local stone to erect the 2.5- to 3.5-meter-high structure, behind which a small pond sprang up. From the pond, a conduit carried water that spilled over a wheel to produce power to run the mill.

Shell tectonics may explain Mars mysteries

Thu, 05 Jan 2012 06:41:58 -0500

This image from the Mars Orbiter Laser Altimeter, which flew onboard the Mars Global Surveyor, shows Olympus Mons and the three Tharsis Montes volcanoes: Arsia Mons, Pavonis Mons, and Ascraeus Mons. NASA

False color image of Mars showing its topography: blues and greens are lowlands, reds are highlands. NASA

Mars may be mythologically known as the Red Planet, but its topography can be as captivating as its celestial glow. Several striking features stand out with only a glance at a topographic map of Mars: the odd distribution of land on its surface and the equatorial string of giant volcanoes known as the Tharsis Rise. Since Mars has no plate tectonics, how these unique features formed has been a longstanding mystery. The answer, scientists now say, may be that instead of many plates sliding across the Red Planet’s surface as we have on Earth, the whole crust of crust moves as a single “shell.”

Stonehenge's Mysterious Stones

Thu, 05 Jan 2012 06:41:58 -0500

Glacial eratics in Canada, such as this giant boulder on the Alberta plains, exemplify how glaciers could have carried giant boulders from mountains in Wales and deposited them on Salisbury Plain. Lionel Jackson

Glaciers once carried giant boulders out of the Canadian Rocky Mountains and moved them hundreds of kilometers southward. Graham Colson

Glaciers carried giant boulders out of the Canadian Rocky Mountains for hundreds of kilometers. Brian John and Lionel Jackson

A tale of glaciers, man, rocks and North America

Storing CO2 in fizzy water underground

Thu, 05 Jan 2012 06:41:58 -0500

Burying carbon dioxide in underground geologic formations is an attractive option for dealing with increasing carbon dioxide in the atmosphere. But before employing such schemes, researchers need to be sure that the greenhouse gas will actually stay put. Scientists have done everything from computer modeling to pumping vast amounts of carbon dioxide into the subsurface to find out if — and how — the gas might be trapped, but gauging how sealed the formations are over geologic time scales is difficult. Now a team of researchers has tried to trace the fate of carbon dioxide in naturally occurring carbon dioxide fields. They found that rather than being stored in the rock itself, the gas mainly dissolved in the formation’s water, a trapping mechanism that should keep the gas securely underground, the researchers say.

Surviving field school: Better than reality TV

Thu, 05 Jan 2012 06:41:58 -0500

Emily points to the embedded dinosaur fossil she discovered in an outcrop of the Morrison Formation. Clay Farris Naff

A closer look at Emily's fossil. Clay Farris Naff

In David Harwood's field course for future teachers, students learn the basics of geology. Kyle Thompson

At a road cut, David (foreground) and Ben ponder the 'layer cakes' above them. Kyle Thompson

David (middle) leads the discussion that solves the Mystery Rock puzzle. Aaron (right) and Chelsea also help. Kyle Thompson

David Harwood’s geology field course for future teachers is not a network reality show — but it should be. The three-week course has all the humor, drama, exacting challenges and bleepable moments of “Survivor.” But in contrast to the staged setups of TV “reality” shows, Geology 160 offers billions of years’ worth of authentic geological history that students see, taste and scrape from under their fingernails.

Swarm of earthquakes rattles Yellowstone

Thu, 05 Jan 2012 06:41:58 -0500

Yellowstone's Excelsior Geyser, in the Midway & Lower Geyser Basin, erupts in July 2001. Jim Peaco, courtesy of the National Park Service

Yellowstone Falls, Wyoming USGS Photo by David E. Wieprecht

An abnormally high number of earthquakes has shaken up Yellowstone National Park in the past week. Since Friday, a “swarm” of more than 250 low-magnitude, shallow quakes has repeatedly rattled an area under Yellowstone Lake, with the highest-magnitude tremor — a magnitude-3.9 quake — on Saturday. The seismic activity has raised fears that the quakes may foreshadow a larger earthquake, or a volcanic eruption — but scientists say there isn’t yet reason to fear an eruption.

The Disappearing Lake

Thu, 05 Jan 2012 06:41:58 -0500

Emily Woodall

For many tourists, Mountain Lake in southwestern Virginia has been an idyllic retreat. But in 2008, it pulled a disappearing act, leaving behind only cracked earth and a small pond.

In this multimedia presentation, EARTH reporter Cassandra Willyard tells the geologic story of Mountain Lake.

The long legacy of Peru's "Mine of Death"

Thu, 05 Jan 2012 06:41:58 -0500

Sediments at the bottom of a small lake 4,600 meters high in the Peruvian Andes archive the history of mining and metallurgy at Huancavelica, the largest mercury deposit in the New World. William Hobbs

Colonial ruins litter the landscape around the Huancavelica mercury deposit. Colin Cooke

Laguna Warmicocha, high in the Peruvian Andes, served as base camp for researchers studying the history of mercury mining and pollution in the Andes. Alberto Reyes

The Inca knew there was something sinister about the cinnabar they hauled out of the ground at Huancavelica in Peru hundreds of years ago. They called the mine the Mine of Death. Now, a new study has exposed a 3,500-year history of mercury pollution from the cinnabar mines, a much longer legacy than researchers had previously realized.

Travels in Geology: Exploring mountains and eating llama in Northern Argentina

Thu, 05 Jan 2012 06:41:58 -0500

Salta is a great place to base your travels through northwestern Argentina. Joshua Zaffos

Humahuaca is a town in the foothills of the Andes with both Incan and Spanish colonial influences. Joshua Zaffos

People have mined salt in the Salinas Grandes for centuries and perhaps millennia. Joshua Zaffos

Cerro Llullaillaco towers above the Puna de Atacama. Federico Manuel Norte, fn@nortetrekking.com

The highway south from Salta toward Cafayate follows the Quebrada de Cafayate, carved by the Río de las Conchas. Federico Manuel Norte, fn@nortetrekking.com

Geology along Quebrada de Cafayate. Joshua Zaffos

Cardón cacti along the Quebrada de Humahuaca. Joshua Zaffos

From cactus-covered deserts to cloud forests to the sky-scraping Andes Mountains, northwestern Argentina promises contrasting landscapes, astounding geological formations and natural beauty — and a chance to eat llama. So with no disrespect to the more geologically famous ice fields and mountains of the Argentine Patagonia to the south, I suggest heading north from Buenos Aires if you get a chance to explore the country.

Travels in Geology: Precipitous peaks and dunes in Colorado

Thu, 05 Jan 2012 06:41:58 -0500

The Sangre de Cristo Mountains border the Great Sand Dunes to the east. Nicole Branan

Majestic snow-capped “fourteeners,” alpine meadows carpeted in wildflowers, pristine mountain lakes. These are the images most people associate with Colorado. One of the best places to experience this rugged wilderness is Rocky Mountain National Park in the northern part of the state.

Travels in Geology: Taking in Hawaii's Big Island

Thu, 05 Jan 2012 06:41:58 -0500

The Big Island of Hawaii, with two snow-topped peaks: Mauna Loa, to the south, and Mauna Kea, to the north. NASA Earth Observatory

For a bit of money, visitors to Hawaii can indulge their touristy impulses with a single night of mai tais and luaus. But take on Hawaii’s geologic hallmarks, and you’ll embark on a low-cost safari that will last you all week.

Underwater basalt formation looks like a city wall

Thu, 05 Jan 2012 06:41:58 -0500

Blogging on EARTH

The concept of sunken, undersea cities has long been present in almost every society, especially in the form of myths such as Atlantis. And now a recent discovery in the Taiwan Strait yields video of a geologic formation that resembles an ancient city wall.

VA geologists axed due to budget crunch

Thu, 05 Jan 2012 06:41:58 -0500

Virginia, like many states, is being hit hard by the recent economic downturn — and as Virginia tightens the purse strings, the state’s geological survey is going to feel the pinch.

Not surprisingly, geologists in Virginia are not happy.