Earthquakes and Plate Tectonics - 2 of 8

Earthquakes and Plate Tectonics FAQs - 8 Found

Foreshocks, aftershocks - what's the difference?

"Foreshock" and "aftershock" are relative terms. Foreshocks are earthquakes that precede larger earthquakes in the same location. Aftershocks are smaller earthquakes that occur in the same general area during the days to years following a larger event or "mainshock." They occur within 1-2 fault lengths away and during the period of time before the background seismicity level has resumed. As a general rule, aftershocks represent minor readjustments along the portion of a fault that slipped at the time of the mainshock. The frequency of these aftershocks decreases with time. Historically, deep earthquakes (>30 km) are much less likely to be followed by aftershocks than shallow earthquakes. (Univ. of Washington)

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Foreshocks, Mainshocks, and Aftershocks Flash AnimationForeshocks, Mainshocks, and Aftershocks Flash Animation

Tags: Seismology, Liquefaction, Tsunamis, Earthquakes, Faults, Tectonics, Magnitude, Prediction