An earthquake is the result from the sudden release of stored energy in the Earth's crust that creates seismic waves.

At the Earth's surface, earthquakes may manifest themselves by a shaking or displacement of the ground. Sometimes, they cause tsunamis, which may lead to loss of life and destruction of property. An earthquake is caused by tectonic plates getting stuck and putting a strain on the ground. The strain becomes so great that rocks give way by breaking and sliding along fault planes.

Earthquakes may occur naturally or as a result of human activities. Smaller earthquakes can also be caused by volcanic activity , landslides, mine blasts, and nuclear tests . In its most generic sense, the word earthquake is used to describe any seismic event—whether a natural phenomenon or an event caused by humans—that generates seismic waves.

WORLD LIST - LOS ANGELES LIST - SHAKE MAP - SAN FRANCISCO LIST
INSTA CALI MAP - EMERGENCY INFO - SEISMO/H'WOOD
WORLD MAP - QUAKE NEWS WIRE - MAMMOTH VOLCANO WATCH







http://www.iris.edu/seismon/