Taxonomy term

march 2015

Magma pancakes underlie Toba supervolcano

Giant eruptions from so-called supervolcanoes eject tremendous volumes of lava and ash, but details about the source of all that volcanic material have been unclear. Now, a new study has found that magma reservoirs intrude into the crust under volcanoes over millions of years in the form of multiple horizontally oriented chambers stacked on top of each other, like a stack of pancakes.

 
11 Mar 2015

Early horse history written in Indian coal mine

Modern horses, rhinos and tapirs — all ungulates with an odd number of toes — belong to a group of animals called Perissodactyla. The oldest Perissodactyla fossils date from the Early Eocene Epoch about 56 million years ago, but the animals’ earlier evolution remains a mystery. Now, a discovery in India suggests that the group likely originated on the Indian subcontinent when it was still an island on a collision course with Asia.

 
10 Mar 2015

Thank subduction for Earth's nitrogen-rich air

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.

 
08 Mar 2015

Lidar reveals Roman gold mines

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.

07 Mar 2015

Sharks collect storm data

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.

06 Mar 2015

Fossil leaves reveal effect of "impact winter"

When the Chicxulub bolide struck the Yucatán Peninsula at the end of the Cretaceous about 66 million years ago, widespread extinctions of land and marine animals resulted. However, the blast’s lasting effects on plants, which tend to be more resilient against impact-related fallout, have been less clear. Now, a new analysis of fossil leaves dating to around the end-Cretaceous offers some of the first quantitative evidence of a substantial shift in plant communities — toward more deciduous plants — following the impact.

05 Mar 2015

El Niño disaster stunted children's growth

In 1997 and 1998, warmer-than-average temperatures brought on by El Niño weather patterns led to copious rainfall and extensive flooding in northern Peru. The rising waters wiped out crops, drowned livestock, cut off bridges, and caused prolonged famine in many rural villages. Now, a new study that tracked long-term health impacts on children from the affected region has found that those born during or soon after the floods continued, a decade later, to bear signs of the hardship endured early in their lives.

 
03 Mar 2015

Where on Earth? - March 2015

Where on Earth was this picture taken? Use these clues to guess and submit your answer via mail, email or Web by the last day of the month (March 31, 2015).

01 Mar 2015

Geologic Column: Lighting out for the territory

The author contemplates the history of westward expansion into arid lands and wonders if our unwise use of resources in places like the U.S. Southwest will eventually return the land "to the process of geology."

27 Feb 2015

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