Earthquake Machine: Elastic Rebound & the Rock Demonstration

Can rock bend? Does rock have elastic rebound?

Demonstration shows that rocks are elastic by squeezing a slit core of solid rock. Energy is stored as potential energy while the rock is squeezed. Energy is released as kinetic energy, and the tongs return to their original position when pressure is released. This is called "elastic rebound" and is what happens along faults in the lithosphere. (John Lahr; USGS seismologist emeritus)


Keypoints:

  • Mechanical model shows how rock behaves when pressure is applied
  • Rock is elastic, therefore the lithosphere is elastic
  • Lithospheric plates behave elastically, like huge springs
  • When elastic energy is released it produces an earthquake releasing heat and kinetic energy


Level: Novice

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