An earthquake is the sudden, rapid shaking of the earth, caused by the breaking and shifting of subterranean rock as it releases strain that has accumulated over time. Earthquakes can happen at any time of the year.

For more information and preparedness actions visit: http://www.ready.gov/earthquakes

To report earthquakes and/or associated shaking and movement please visit USGS Did You Feel It at: http://earthquake.usgs.gov/earthquakes/