Seismology investigates the propagation of elastic/acoustic waves through solid and semi-solid planetary bodies. Seismic waves are usually thought of as having their origins in movements associated with earthquakes. Seismology uses the principles of wave propagation to infer properties and characteristics of the Earth's Interior. A recently developed procedure for doing this involves seismic tomography. Tomographic studies help to reveal velocity variations (and hence density variations) within the Earth's mantle. Also see the related page on Planetary Interiors.



Earthquake location and depth maps for:


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Last Modified: August 15, 2001