​One of the most frightening and destructive phenomena of nature is a severe earthquake and its terrible aftereffects. 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 a long time.

All 50 states and 5 U.S. territories are at some risk for earthquakes. Earthquakes can happen at any time of the year. Seismic activity is unusual in Maryland, but several minor quakes have hit Maryland in the last decade.