Why do most earthquakes occur at tectonic plate boundaries

Notice that many plate boundaries do not coincide with coastlines. Earthquakes can also occur far from the edges of plates, along faults. Faults are cracks in the earth where sections of a plate (or two plates) are moving in different directions. Faults are caused by all that bumping and sliding the plates do.

1/0.14nm = 10^10/1.4 a lot

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