Earthquakes are sudden rolling or shaking events caused by movement under the earth’s surface. Earthquakes happen along cracks in the earth's surface, called fault lines, and can be felt over large areas, although they usually last less than one minute. Earthquakes cannot be predicted — although scientists are working on it!
All 50 states and 5 U.S. territories are at some risk for earthquakes. Earthquakes can happen at any time of the year.