The release of stored energy from rocks that are deformed by stress is called elastic

The given blank can be filled with rebound.  

The elastic rebound theory refers to an illustration for how energy is discharged at the time of earthquakes. As rocks on opposite ends of a fault are subjected to force and shift, they gather energy and gradually deform until their inner strength is exceeded.  

As adjacent plates on the surface of the Earth move in reverse orientations, the rocks that cover the opposing ends of the incipient fault are imperiled to extreme shear stress.  

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