ESCI 2010 Chapter Notes - Chapter 4: Epicenter, Seismic Wave, Transform Fault

• School: University of Windsor
• Department: Earth and Environmental Sciences
• Course: ESCI 2010
• Professor: Frank Simpson

Document Summary

Earthquakes represent a release of built-up stress in the lithosphere. They occur along faults, planar breaks in rock along which there is displacement of one side relative to the other. Sometimes, stress produces new faults or breaks; sometimes, it causes slipping along old, existing faults. When movement along fault occurs gradually and relatively smoothly, it is called creep (aseismic slip: fault displacement without significant earthquake activity. When friction between rocks on either side of a fault prevents the rocks from slipping easily or when the rock under stress is not already fractured, some elastic deformation will occur before failure. When stress exceeds rupture strength of the rock (or the friction along a preexisting fault), a sudden movement occurs to release the stress: this is an earthquake, or seismic slip. When the sudden displace and associated stress release, the rocks snap back elastically to their previous dimensions; this behaviour is called elastic rebound.