1 / 14

How many Earthquakes Occur each year??

How many Earthquakes Occur each year??. More than 1 million !!!. What are Earthquakes?. Vibrations of the earth’s crust caused by a sudden release of energy. What causes EQ’s? . Build up of stress along the boundaries of tectonic plates. Stress.

amelia
Télécharger la présentation

How many Earthquakes Occur each year??

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. How many Earthquakes Occur each year?? More than 1 million !!!

  2. What are Earthquakes? Vibrations of the earth’s crust caused by a sudden release of energy

  3. What causes EQ’s? Build up of stress along the boundaries of tectonic plates

  4. Stress Stress = the total force acting on crustal rocks per unit of area 3 Kinds of stress • Compression – decrease volume • Tension – pulls apart • Shear – twist Example : sponge

  5. Strain How rocks respond to stress is called strain Strain= deformation of a material expressed in rocks by folding (bending) or faulting (breaking)

  6. Elastic Rebound Theory Describes the process between stress & strain

  7. Elastic Rebound Theory • 2 sides along a fault are locked by friction • Energy in the form of stress is stored in rock • When stress exceeds frictional lock, movement occurs • Energy is released in form of waves • Rocks rebound to original shape

  8. Elastic Rebound Theory Demo:

  9. Wood blocks, sandpaper, and rubber bands, can model the slow storage and rapid release of elastic energy

  10. In Class • Read text p 528 – 530 • Define stress & strain

  11. ANY QUESTIONS?

More Related