Scientists have discovered that a North Korean nuclear bomb test last fall set off aftershocks over a period of eight months on a previously unmapped earthquake fault nearby.

In a new study, researchers report that their physics-based model of California earthquake hazards replicated estimates from the state’s leading statistical model.

An extensive investigation has found that many children living on U.S. military bases may be exposed to hazardous levels of lead in decaying family housing.

Tiny microbes called phytoplankton live beneath the ocean’s surface, producing oxygen that is essential to human survival. A new study sheds light on how these all-important diatoms survive and thrive under difficult conditions.

Geochemist Alex Halliday was appointed the new director of Columbia’s Earth Institute by University President Lee C. Bollinger last December.