Earthquake Machine: Elastic Rebound & the Rock Demonstration

Can rocks bend? Do rocks have elastic rebound?

This 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)


  • Mechanical model shows how rocks behave when pressure is applied
  • Rocks are 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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