Hawaiian Islands: Origin of Earthquakes

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From our knowledge of earthquake history in Hawai’i, we can calculate the shaking or seismic hazard from large earthquakes. In the hazard map, warm colors, seen mostly on the Island of Hawai’i, indicate the highest seismic hazard in the state, comparable to that along the San Andreas fault zone of California. Seismic hazard decreases northwestward along the Hawaiian island chain, as shown by cooler colors, but it remains significant as far northwest as O’ahu.

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Keypoints:

Earthquakes occur in three regions:

  • In the volcanoes
  • Along the volcano-ocean floor boundary
  • In the mantle

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