The underground effects of earthquakes and volcanoes

Most of what we know about earthquakes and volcanoes is based on what we can observe at the Earth's surface. However, most of the action, especially early activity that could help with disaster prediction and preparedness, ...

Homing in on a potential pre-quake signal

In a new analysis of the 2004 magnitude 6.0 Parkfield earthquake in California, David Schaff suggests some limits on how changes measured by ambient seismic noise could be used as a pre-earthquake signal.

In Japan, seismic waves slower after rain, large earthquakes

An earthquake is first detected by the abrupt side-to-side jolt of a passing primary wave. Lagging only slightly behind are shear waves, which radiate out from the earthquake's epicenter and are seen at the surface as a rolling ...