Fault: Normal

How does a normal fault move?

In a normal fault, the block above the fault moves down relative to the block below the fault. This fault motion is caused by tensional forces and results in extension. Other names: normal-slip fault, tensional fault or gravity fault. Examples: Sierra Nevada/Owens Valley; Basin & Range faults.


Keypoints:

  • The block above the fault moves down relative to the block below the fault
  • Fault motion is caused by tensional forces that result in extension.

Total Time: 11s
Level: Novice

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Silly Putty™ allows students to discover that the structure we see in rocks provides evidence for they type of stress that formed. Students apply this idea by examining images of faults and folds experimentation with sponge models.

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How can I demonstrate plate tectonic principles in the classroom?

Video lecture demonstrates the use of foam faults to demonstrate faults, and a deck of cards to demonstrate folds and fabrics in rock layers. Different types of faults include: normal (extensional) faults; reverse or thrust (compressional) faults; and strike-slip (shearing) faults.

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