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Earthquakes are caused by the release of built-up pressure inside the Earth's crust. The effects can cause deaths, destroy settlements and change landscapes. Watch this video to find out more.


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Key points

  • Earthquakes are the vibration of the crust due to movement of tectonic plates.
  • The focus is the point inside the Earth's crust where the pressure is released. The epicentre is the point above the focus, on the Earth's surface. The most severe damage will happen close to the epicentre.
  • The power of an earthquake is measured using a seismometer which plots vibrations on a seismograph.
  • The strength of an earthquake is measured on the Richter scale which is numbered 0-10. An Earthquake measuring seven or eight can be devastating.
  • LEDCs often suffer more from the effects of volcanoes and earthquakes. This is because they have weaker communication systems, lower standard of buildings and less funds for evacuation and eventual aftermath.

All Geography videos

Natural hazards index

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