Asperity on a Fault

Why don't faults keep sliding past each other?

Map view looking down on a fault zone with a single asperity. Regional right lateral strain puts stress on the fault zone. A single asperity resists movement of the green line which deforms before finally rupturing.


Keypoints:

  • An asperity is an area on a fault that is stuck or locked.
  • An area along an active fault that has not had an earthquake in a long time might be vulnerable to a large earthquake.
  • On a long fault, adjacent areas may move, putting strain on the asperity

Total Time: 13s
Level: Novice

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