San_Adreas_Fault

San Adreas Fault December 5, 2001 San Andreas Fault Introduction The San Andreas Fault is a geologic fault zone between two tectonic plates that runs from San Francisco south to San Diego in California. It is an area of frequent earthquakes caused by the plates sliding past each other. It is so called because it runs along the San Andreas Valley. The San Andreas fault was brought dramatically to world attention in 1906 when sudden displacement along the fault produced the great San Francisco earthquake and fire. This earthquake was but one of many that have resulted throughout its life of about 15-20 million years. Body The entire San Andreas fault system is more than 800 miles long and extends to depths of at least 10 miles within the Earth. The fault is a complex zone of crushed and broken rock from a few hundred feet to a mile wide. Many smaller faults branch from and join the San Andreas fault zone. The Pacific plate is moving northwest in relation to the North American plate, and it is believed that the total displacement along the fault since its formation more than 30 million years ago has been about 350 mi. Movement along fault, san, andreas, plates, earthquakes, time, along, zone, years, plate, north, miles, faults, earth, understand, two, tectonic, south, scientists, runs, rock, pacific, one, moving, million, geologic, francisco, earthquake, each, displacement, broken, because, american, about, world