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San Andreas Fault

San Andreas Fault is a geological fault that spans a length of roughly 800 miles (1287 kilometres) through California, United States. The fault, a right-lateral strike-slip fault, marks a transform boundary between the Pacific Plate and the North American Plate. All land west of the fault on the Pacific Plate is moving slowly to the northwest while all land east of the fault is moving to the southwest (relatively southeast as measured at the fault) under the influence of plate tectonics. The rate of slippage is approximately of 1/5 inch (0.6 cm) a year. Projected motion indicates that the Gulf of California will expand northward at the same time that the landmass west of the fault, including the Baja California peninsula and the California coast (including Los Angeles) slides past San Francisco, then continuing northwestward as an island mass toward the Aleutian Trench, over a period of perhaps twenty million years.

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