Earthquake Terms

Seismology The study of Earthquakes

Faults A break in the Earth’s crust along which blocks of the crust slide relative to one another Earthquakes occur along faults because of this sliding.

Deformation – bending and breaking of Earth’s crust Plastic deformation Elastic deformation Like a piece of molded clay Does not lead to earthquakes Like a rubberband Sudden return of elastically deformed rock to its undeformed shape Energy is released Seismic waves cause Earthquakes

A wave of energy that travels through the Earth. Seismic Waves A wave of energy that travels through the Earth.

P waves S Waves A seismic wave that causes particles of rock to move in a back-and forth motion Primary waves – pressure waves Fastest waves Can travel through solids, liquids, and gases A seismic wave that causes particles of rock to move in a side-to- side motion Secondary waves – shear waves Second fastest waves Cannot travel through liquid

Surface Waves They move along the Earth’s surface and produce motion mostly in the upper few kilometers of Earth’s crust. They move the ground much like ocean waves move water. Travel more slow More destructive