Chapter 7.1

Who contributed greatly to our understanding of the mechanism of earthquake generation by proposing the Elastic Rebound Theory?

Reid; The vibrations we know as earthquakes occur as the rock elastically returns to its original shape after breakage.

Energy released from an earthquake event is mostly in the form of

seismic waves

Most earthquakes are caused by

slippage along a fault

After rupture occurs along a fault, rocks continue to deform indefinitely from the release of energy.

False; After rupture or the initial slippage of rocks, rocks elastically return to their original shape.

Fires after the 1989 Loma Prieta Earthquake were responsible for most of the fatalities.

False; Fires were responsible for a lot of the damage during the 1906 San Francisco Earthquake, but the freeways proved most dangerous for the more recent Loma Prieta Earthquake.

All earthquakes occur along faults associated with plate boundaries.

False; Most but not all earthquakes occur at or near plate boundaries, but historically there have been some earthquakes that occur within the interior of continents away from plate boundaries.

Earth's crust has been uplifted several times.

True; Ancient wave-cut benches on the West Coast of the United States provide examples.

Most of the motion along faults can be explained by Plate Tectonics.

True; Most plate boundaries are characterized by one or more types of faults.

Major earthquakes are often preceded by a series of small vibrations called

foreshocks; These may be useful for predictions but more studies are needed.