Taxonomy term

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.

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.

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.

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.