Hypocenter

The hypocenter (literally: 'below the center') is the site of an earthquake or a nuclear explosion. In an earthquake, it is a synonym of the focus and is directly below the epicenter.The hypocenter is the point within the earth where an earthquake rupture starts. The epicenter is the point directly above it at the surface of the Earth. Also commonly termed the focus. "Earthquake Glossary - hypocenter". United States Geological Survey. Archived from the original on 15 March 2010.  In the case of a nuclear explosion, it is a synonym of ground zero.

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Category:Earth sciences