Movement occurs along fractures in rocks when <u>stress overcomes the strength of the rocks involved.</u>
Explanation:
The fracture that occurs in rocks is called a fault. The movement is due to more stress on the rocks that are of lesser strength.
Rocks are elastic in nature. Faults occur because of stress that builds up, causing deformations. When stress increases eventually, it overcomes the strength of the rocks and energy releases, resulting in earthquakes.
Tsunami occurs in oceans when rock bed shift underneath, causing huge waves.
Due to sudden breaks on the rocks under the earth, an explosion occurs that produces energy waves called the Seismic waves.
