Why are earthquakes?

Earthquakes are tremors and vibrations of the Earth’s surface caused by natural causes (mainly tectonic processes) or artificial processes (explosions, filling reservoirs, collapse of underground cavities of mine workings). Small tremors can also cause the rise of lava during volcanic eruptions.
About a million earthquakes occur throughout the Earth every year, but most of them are so insignificant that they go unnoticed. Really strong earthquakes that can cause extensive destruction occur on the planet about once every two weeks. Fortunately, most of them fall to the bottom of the oceans, and therefore are not accompanied by catastrophic consequences (if an earthquake under the ocean does without a tsunami).
Earthquakes are best known for the devastations they are capable of producing. Destruction of buildings and structures is caused by vibrations of the soil or giant tidal waves (tsunamis) that occur during seismic displacements on the seabed.

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