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Visual Glossary

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Earthquake
Epicenter
Focus

Earthquake-A sudden ground motion or vibration produced by a rapid release of stored-up energy.

Epicenter-The point on the Earth’s surface located directly above the focus of an earthquake.

Focus-The location where the earthquake begins. The ground ruptures at this spot, then seismic waves radiate outward in all directions.

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This page was last updated on 9/6/00