GEOL105 Chapter Notes - Chapter 2: Seismic Moment, 32X, Mercalli Intensity Scale

• School: University of Delaware
• Department: Geology
• Course: GEOL105
• Professor: John Polk

Document Summary

Earthquakes: vibrations (mechanical waves) felt throughout the earth. Fault: a fracture in the crust along which there has been movement (displacement). Not a part of plate tectonics: they do play a big role in volcanism. Areas of extra uplift and heat from mantle. Caused by movement along faults, volcanic eruptions, explosions, and impacts (from large objects from outer space). If the movement is sudden, seismic waves are released. You need to have stress to move fault blocks. Fault types are based on fault block movement. There are strikes on the fault block and the dip is used to find the angle of the fault based on the strike. Hanging wall: the side over the head. Footwall: the side that is under the feet. Normal fault: sides move vertically and away from each other, tension, stress away from the fault, hanging wall moves down, footwall up.