Taxonomy term

april 2016

Where fire freezes: All eyes, ears and instruments on Iceland's volatile volcanoes

With examples of every type of volcano on Earth — each with its own eruptive pattern — Iceland presents a special challenge to volcanologists, but also serves as an ideal natural laboratory for studying how volcanic processes evolve.

29 Mar 2016

Eerily quiet Katla

Katla Volcano is located near the southern tip of Iceland, under the Mýrdals­jökull Ice Cap. Ashfall deposits found as far away as Norway and Denmark indicate that Katla erupted at least 20 times between A.D. 930 and the last eruption in 1918. Its present dormancy is the longest-known quiet period in the volcano’s history.

29 Mar 2016

Hekla the heckler

Hekla is one of Iceland’s most active volcanoes, erupting more than 25 times since its first recorded eruption in 1104. The most recent eruptions in 1970, 1980, 1981, 1991 and 2000 have allowed geoscientists to create a detailed eruption profile for the volcano.

29 Mar 2016

King Oraefajokull

The Öraefajökull Volcano boasts Iceland’s highest peak — 2,109 meters above sea level — and has the reputation of being Iceland’s largest and most violent volcano. Major eruptions in 1362 and 1727 were among the most explosive in the island’s history, and both were accompanied by catastrophic glacial floods. After the 1362 event, the Icelandic word öraefi, originally meaning “area without a harbor,” was rechristened to mean “wasteland.”

29 Mar 2016

Lunar atmosphere more active than we thought

LADEE — pronounced “laddie” and short for Lunar Atmosphere and Dust Environment Explorer — was among the shortest-lived of NASA’s successful satellites. Launched on Sept. 7, 2013, it crashed onto the moon’s surface, as intended, on April 17, 2014, after six months orbiting the moon. Data collected by LADEE have already greatly expanded our understanding of the atmosphere of the moon and other bodies in the solar system; the spacecraft also made a number of unexpected discoveries, some of which were presented at the fall meeting of the American Geophysical Union (AGU) in San Francisco last December.

28 Mar 2016

Going with the flow: Mapping the mantle under the Cascadia Subduction Zone

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.

25 Mar 2016

Underground ants can't take the heat

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.

24 Mar 2016

A long layover on the Bering land bridge

About 11,500 years ago, two infants were laid to rest side by side in a shallow grave 80 kilometers southeast of what is now Fairbanks, Alaska. The area was once part of Beringia, a strip of ice-free land connected to Asia during the last ice age. Researchers found the remains in 2013, and have now sequenced the complete mitochondrial genomes of the two children. The results revealed that the infants had different mothers and that their genetic signatures are found today throughout North and South America.

23 Mar 2016

Mass measured for smallest exoplanet yet

By the late 19th century, astronomers had calculated correctly that Mars — about half the diameter of Earth — holds roughly one-tenth the mass of Earth, whereas its density is about 71 percent that of our planet. These fundamental planetary traits have also long been known for Mercury and Venus. But measuring the masses and densities of the many roughly Earth-sized exoplanets discovered lately — which, to space telescopes, appear as mere specks as they pass in front of, or transit, their home stars — has proved challenging.

22 Mar 2016

Travels in Geology: Gotland getaway: Sweden's 'tropical' escape in the Baltic

Gotland, a Silurian-aged coral-reef island with white sand beaches, lies not in the tropics but in the Baltic Sea off the southeastern coast of Sweden just a short trip from Stockholm. In addition to the carbonate geology, visitors can view medieval churches and thatched-roof Viking farms, and experience the moody, atmospheric weather featured in the films of director Ingmar Bergman.

21 Mar 2016