The term geology refers, according to Britannica, the fields of study concerned with the solid Earth. San Andreas is probably the most famous fault line in California because of the damage it has done and will likely still cause because we are due for the big one. Offset Drainage: Aerial photo of the San Andreas Fault showing drainage that is offset by movement of the fault. Be on the lookout for your Britannica newsletter to get trusted stories delivered right to your inbox. It’s actually very active and is the fastest slipping fault for the San Andreas in Southern California. Suddenly the built-up strain breaks the rock along the fault, and the plates slip a few feet all at once. The fault moves via tectonic plates sliding past each other horizontally. Omissions? With Californiaâs large population and temperate climate, there are many roads that snake along the fault. The fault trends northwestward for more than 800 miles (1,300 km) from the northern end of the Gulf of California through western California, U.S., passing seaward into the Pacific Ocean in the vicinity of San Francisco. The San Andreas Fault is known as a transform fault, which is where two of the earth's plates meet. Photo: San Andreas Fault. It’s America’s most dangerous fault and the fear of a huge earthquake from the San Andreas has been a major subject for disaster films, such as Superman and, more recently, San Andreas. “This particular strand of the San Andreas failure has been interpreted to be not very active. The entire San Andreas fault system is more than 800 miles long and extends to depths of at least 10 miles within the Earth. It is classified as a right lateral (dextral) strike-slip fault. Text Only Version The San Andreas Fault. From street and road map to high-resolution satellite imagery of San Andreas Fault. The arrows show the directions of relative motion along the fault. Choose from several map styles. State and National parks are strung along the fault like beads on a string. Some cities, towns, housing developments, and roads are actually built on it, and a tunnel of the San Francisco Bay Area Rapid Transit System (BART) is bored right through the fault zone. The location of the San Andreas Fault is shown on this map. It slices California in two from Cape Mendocino to the Mexican border. The book contains twelve one-day driving trips along different parts of the fault, and includes mile-by-mile road logs and GPS coordinates for hundreds of fault features. The breaking rock sends out waves in all directions, and it is the waves that we feel as earthquakes. San Andreas Map: The red line on this map follows the surface trace of the San Andreas Fault across California. San Andreas is a 2015 American disaster film directed by Brad Peyton and written by Carlton Cuse, with Andre Fabrizio and Jeremy Passmore receiving story credit.The film stars Dwayne Johnson, Carla Gugino, Alexandra Daddario, Ioan Gruffudd, Archie Panjabi, and Paul Giamatti.Its plot centers on an earthquake caused by the San Andreas Fault devastating Los Angeles and the San Francisco Bay Area. The fault trends northwestward for more than 800 miles (1,300 km) from the northern end of the Gulf of California through western California, U.S., passing seaward into the Pacific Ocean in the vicinity of San Francisco. By signing up for this email, you are agreeing to news, offers, and information from Encyclopaedia Britannica. The San Andreas Fault is a continental transform fault that spans 750 miles through California. How solid is your knowledge of all things geological? Pinnacles National Monument in Monterey County is only half of a volcanic complex, the other part being 200 miles southeast in Los Angeles County and known as the Neenach Volcanics. And despite San Franciscos legendary 1906 earthquake, the San Andreas Fault does not go through the city. The San Andreas Fault is a continental transform fault that extends roughly 1300 km (810 miles) through California. Our editors will review what you’ve submitted and determine whether to revise the article. While not unheard of globally, earthquakes of this size are generally confined to regions of the earth where subduction – one tectonic plate is being forced below another – is … With about 45 years between the historic earthquakes but about 160 years since the last one, it is clear that the fault does … Tectonic plates are what make up the Earth’s crust where the oceans and continents rest on. But how big could this potential earthquake […] San Francisco, Sacramento and the Sierra Nevada are on the North American Plate. Test your knowledge by taking this quiz. Its trace is marked by red dots connected by thin red straight lines. The positions were measured from professional geological maps, primarily those of the United States Geological Survey, California Geological Survey, … Parts of the fault line moved as much as 6.4 metres (21 feet) during the 1906 earthquake. The hallmark of the San Andreas Fault is the different rocks on either side of it. The great majority of California’s population lives in the vicinity of the San Andreas Fault. Ring in the new year with a Britannica Membership, This article was most recently revised and updated by, https://www.britannica.com/place/San-Andreas-Fault, San Andreas Fault Homepage - Information, Photos, Maps, and More, San Andreas Fault - Student Encyclopedia (Ages 11 and up). For years the plates will be locked with no movement at all as they push against one another. Photo of the San Andreas Fault near Gorman, California, showing rocks of the Pacific Plate (gray rocks on the left side of the fault) and the North American Plate (tan rocks on the right side of the fault). The movement of the plates relative to each other has been about 1 cm (0.4 inch) per year over geologic time, though the annual rate of movement has been 4 to 6 cm (1.6 to 2.4 inches) per year since the early 20th century. It slices California in two from Cape Mendocino to the Mexican border. In many places like the Carrizo Plain (San Luis Obispo County) and the Olema Trough (Marin County), the fault is easy to see as a series of scarps and pressure ridges. Latest news: earthquakes, volcanic eruptions, tsunamisand San Andreas fault. The San Andreas Fault is the sliding boundary between the Pacific Plate and the North American Plate. The San Andreas fault's nick name is "SAF". Scientists call main areas of tension 'strands', where collisions between plates produce dramatic … Sandra S. Schulz and Robert E. Wallace San Andreas fault in the Carrizo Plain, central California (Photo by Robert E. Wallace) Areas to the west (left) of the fault are part of the Pacific tectonic plate. Photograph copyright by David Lynch. The San Andreas Fault is more accessible than any other fault in the world. Let us know if you have suggestions to improve this article (requires login). Visiting the fault is easy. David K. Lynch, PhD, is an astronomer and planetary scientist living in Topanga, CA. Updates? But this is not a steady motion, it is the average motion. In other places, it is more subtle because the fault hasnât moved in many years and is covered with alluvium, or overgrown with brush. 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