Focal mechanism

Process that generates seismic waves in an earthquake

The focal mechanism of an earthquake describes the deformation in the source region that generates the seismic waves. In the case of a fault-related event, it refers to the orientation of the fault plane that slipped, and the slip vector and is also known as a fault-plane solution. Focal mechanisms are derived from a solution of the moment tensor for the earthquake, which itself is estimated by an analysis of observed seismic waveforms.

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