Taxonomy term

mary caperton morton

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

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

Hidden double earthquake spells trouble for tsunami-warning systems

On Jan. 2, 2011, a magnitude-7.1 earthquake was recorded striking central Chile along the tectonic boundary between the Nazca and South American plates. Shaking from the quake was felt hundreds of kilometers from the epicenter, but no deaths or major damage were reported.
 
06 Mar 2016

Himalayas get a new birthdate

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.

05 Mar 2016

How supervolcanoes are set off

If a supervolcano were to erupt today, its impacts could be catastrophic. Fortunately, no such eruption has occurred during human history. The lack of eyewitness accounts, however, makes it difficult for scientists to understand how supervolcanoes evolve and erupt. Based on a recent modeling, researchers have offered a new hypothesis for how supervolcano eruptions might be triggered by external, rather than internal, forces.

01 Mar 2016

Earliest Americans were wide-ranging wanderers

About 40 years ago, when the Monte Verde archaeological site in southern Chile was dated to 14,800 years ago, conventional ideas of American anthropology were turned on their heads. Until then, the “Clovis First” theory, which held that modern humans only began populating the Americas from Asia via the Bering land bridge roughly 13,500 years ago, was widely accepted. That people had lived thousands of kilometers farther south more than 1,000 years before the Clovis culture arose came as a shock initially, but the idea, and the Monte Verde site, has gradually become accepted over time.

27 Feb 2016

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