Taxonomy term

mary caperton morton

Mediterranean tsunami record may be overreported

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.

18 Jan 2018

Small warm ponds: Ideal incubators for first life?

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.

17 Jan 2018

It's an asteroid, no wait, a comet, no wait…

NASA’s Hubble Space Telescope has spied a unique object in the debris-filled asteroid belt between Mars and Jupiter: a pair of asteroids — orbiting tightly around each other — that also show comet-like characteristics, including a bright halo of ice and dust known as a coma and a long tail of dust. The odd object, called 2006 VW139/288P, is the first known binary asteroid that is also classified as a main-belt comet.

12 Jan 2018

In feats of tectonic strength, grain size matters

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.

04 Jan 2018

Fossilized dinosaur feces reveal flexitarian diet

Fossilized feces tell paleontologists a lot about what dinosaurs ate. Some unusual coprolites discovered in Utah’s Grand Staircase-Escalante National Monument may indicate that normally herbivorous dinosaurs occasionally ate crustaceans.

03 Jan 2018

Science meets art: Tiny trilobite gets huge makeover

At less than a centimeter in size, Agnostus pisiformis might not look like much, but a new series of larger-than-life sculptures is giving the arthropod its due as one of the most ubiquitous and recognizable Cambrian fossils.

01 Jan 2018

Turkey DNA reveals Mesa Verde denizens moved to New Mexico

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.

28 Dec 2017

Mysterious Miocene bipedal footprints found in Crete

A curious set of 5.7-million-year-old bipedal footprints found in western Crete — far from the cradle of humanity in Africa and dating to the Late Miocene, long before hominins are thought to have walked upright — has paleoanthropologists scratching their heads.

27 Dec 2017

Volcanism spiked global temps during past hothouse

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.

25 Dec 2017

New Zealand quake triggers two large slow-slip events

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.

21 Dec 2017

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