notorious earthquake fault in North America is the San Andreas Fault that runs through
California. The 1,300 kilometer (800 mile) long fault is the transform boundary between the
northeastward-moving Pacific plate and the southwestward-moving North American plate.
The San Andreas is a right-lateral strike-slip fault (Figure7.29).
Figure 7.29: The San Andreas Fault runs up western California. It is the transform plate
boundary between the northwestward moving Pacific Plate and the southeastern moving
North American Plate. ( 10 )
The largest earthquake on the San Andreas Fault in historic times occurred in 1906 in San
Francisco (Figure7.30). This earthquake likely measured magnitude 7.8, which is a very
large earthquake. The earthquake and the subsequent fire is still the most costly natural
disaster in California history. An estimated 3,000 people died and about 28,000 buildings
were lost, mostly in the fire.