What term describes the elastic rebound mechanism that releases strain during many earthquakes?

Elastic rebound theory describes how accumulated strain is suddenly released during many earthquakes.

Tectonic forces slowly deform rocks on opposite sides of a fault. Friction can lock the fault even while the surrounding crust continues to bend and store elastic energy. When the stress exceeds the fault’s strength, the rocks slip toward a less-deformed position, releasing energy as seismic waves.

American geologist Harry Fielding Reid developed the theory after studying the 1906 San Francisco earthquake. Survey measurements showed that the ground had shifted on either side of the San Andreas Fault, supporting the idea that crustal strain had built up before rupture.

Elastic rebound does not mean every earthquake occurs on the same kind of fault. Normal, reverse, and strike-slip faults can all release stored strain. The theory also explains why land may move suddenly after years or centuries of comparatively slow deformation.