The San Andreas Fault is a continental right-lateral strike-slip transform fault that extends roughly 1,200 kilometers (750 mi) through the U.S. state of California. It forms part of the tectonic boundary between the Pacific Plate and … See more

The San Andreas began to form in the mid Cenozoic about 30 Mya (million years ago). At this time, a spreading center between the Pacific … See more

The San Andreas Fault has had some notable earthquakes in historic times:
• 1857 Fort Tejon earthquake: About 350 kilometers (220 mi) were ruptured in central and southern California. Though it is known as the Fort Tejon earthquake, the epicenter is … See more

Northern
The northern segment of the fault runs from Hollister, through the Santa Cruz Mountains, epicenter of the 1989 Loma Prieta earthquake, then up the San Francisco Peninsula, where it was first identified by See more

The Pacific Plate, to the west of the fault, is moving in a northwest direction while the North American Plate to the east is moving toward the southwest, but relatively southeast … See more

Early years
The fault was first identified in Northern California by UC Berkeley geology professor Andrew Lawson in 1895 and named by him after the surrounding San Andreas valley. Eleven years later, Lawson discovered … See more

• San Francisco Bay Area portal
• Earth sciences portal
• California earthquake forecast – 2015 US Geological Survey earthquake forecast for California
• Central Valley (California) – Flat valley that … See more