Aftershock - a small earthquake or tremor that follows a major earthquake.
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Body Waves - a transverse or longitudinal earthquake wave that travels through the interior of the earth
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Earthquake - a series of vibrations induced in the earth's crust by the abrupt rupture and rebound of rocks in which elastic strain has been slowly accumulating.
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Epicenter - a point, directly above the true center of disturbance, from which the shock waves of an earthquake apparently radiate.
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Fault - a defect or imperfection; flaw; failing
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Focus - a central point, as of attraction, attention, or activity
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Liquefaction - the act or process of liquefying or making liquid
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Magnitude - size; extent; dimensions
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P waves - a longitudinal earthquake wave that travels through the interior of the earth and is usually the first conspicuous wave to be recorded by a seismograph.
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S waves - a transverse earthquake wave that travels through the interior of the earth and is usually the second conspicuous wave to reach a seismograph.
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Seismic gap - the part of an active fault that has experienced little or no seismic activity for a long period, indicating the buildup of stresses that are useful in predicting earthquakes.
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Seismogram - a record made by a seismograph.
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Seismograph - any of various instruments for measuring and recording the vibrations of earthquakes.
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Surface waves - a seismic wave that travels along or parallel to the earth's surface
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Tsunami - an unusually large sea wave produced by a seaquake or undersea volcanic eruption.
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