Geology

What makes volcanoes dangerous?

Recent eruptions offer reminders that lava, ash and size don’t fully explain how volcanoes become deadly.

Overpumping groundwater increases contamination risk

Pumping an aquifer to the last drop squeezes out more than water. A Stanford study finds it can also unlock dangerous arsenic from buried clays – and reveals how sinking land can provide an early warning and measure of contamination.

Sterol-producing bacteria may change interpretation of geological history

Geologists assume when they find molecules called sterols in soils or rocks they indicate the presence of plants, animals or fungi in ancient environments. In new research from Paula Welander, discovering how some bacteria also produce and modify sterols could change those interpretations.

Aquatic mammals need to be big, but not too big

Examining body sizes of ancient and modern aquatic mammals and their terrestrial counterparts reveals that life in water restricts mammals to a narrow range of body sizes – big enough to stay warm, but not so big they can’t find enough food.

New map profiles induced earthquake risk

A map created by Stanford geophysicists can help predict which parts of West Texas and New Mexico may be at risk of fracking-induced earthquakes. The map could guide oil discovery efforts in the region.

Insects took off when they evolved wings

Now buzzing and whizzing around every continent, insects were mysteriously scarce in the fossil record until 325 million years ago – when they first took flight and, according to a new study, evolutionarily took off.