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Plate margins and plate tectonics - AQAGlobal distribution of earthquakes and volcanoes

Earthquakes and volcanic eruptions affect people all over the world. They are caused by the movement of tectonic plates. Tectonic hazards can destroy buildings, infrastructure and cause deaths.

Part of GeographyThe challenge of natural hazards

Global distribution of earthquakes and volcanoes

The earth's surface is made up of two types of crust:

  • - found underneath the oceans. It is denser than continental crust and can be subducted.
  • - found under land masses or continents. It is generally older than oceanic crust and is less often destroyed.

Earthquakes are found along all types of as shown on this map. Volcanoes however, only occur at constructive and destructive plate margins.

[A] Most earthquakes happen along fault lines. [B] Most volcanoes appear on plate boundaries.
[A] Most earthquakes happen along fault lines. [B] Most volcanoes appear on plate boundaries.

Hawaii is an arc of volcanic islands, found above a hot spot.