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88-569: The Hosgri Fault is a component of the San Andreas Fault system. Its movement is primarily reverse thrust , as well as exhibiting right lateral slip, and is thought to be capable of generating earthquakes of up to magnitude 7.5. The November 4, 1927 Lompoc earthquake (magnitude 7.1) is thought to have occurred (uncertainty) on this fault. Seismologists monitor activity on the Hosgri fault constantly because of its physical proximity to

176-644: A California earthquake forecast, which models earthquake occurrence in California. This is a partial list of earthquakes in Southern California. For a full list, see List of earthquakes in California . Note: Earthquakes with epicenters in the Los Angeles Metro Area are marked with the (#) symbol. Other earthquakes mentioned indicates shaking was felt in the region. As of the 2020 United States Census , Southern California has

264-591: A M w   6.7 earthquake or greater, such as the San Andreas Fault , which can produce M w   8.0 or greater. The largest known earthquake in California was the 1857 Fort Tejon earthquake that ruptured 200+ miles (320+ kilometers) of the San Andreas Fault from Parkfield to Wrightwood . With a recurrence interval of roughly 150 years, this part of the San Andreas fault is well within its window to produce another large earthquake. Along with

352-595: A higher population, with 23.76 million residents as of the 2020 census . The sparsely populated desert region of California occupies a significant portion (part of which has even been proposed to be split into a new county due to cultural, economic and geographic differences relative to the rest of the more urban region) of the area: the Colorado Desert , along with the Colorado River , is located on Southern California's eastern border with Arizona , and

440-560: A link between the water level in Lake Cahuilla (now the Salton Sea ) and seismic activity along the southern San Andreas Fault. The study suggests that major earthquakes along this section of the fault coincided with high water levels in the lake. The hydrological load caused by high water levels can more than double the stress on the southern San Andreas Fault, which is likely sufficient for triggering earthquakes. This may explain

528-495: A magnitude 7.8 earthquake along the southern San Andreas Fault could cause about 1,800 deaths and $ 213 billion in damage. This scenario hypothesizes the potential effects of a 7.0 magnitude earthquake on the San Andreas Fault in the San Francisco Bay Area. It aims to estimate the impacts on urban infrastructures along with the rebuilding efforts to both the landscape and economy. This study combines not only

616-611: A population of 23,762,904. Despite a reputation for high growth rates, Southern California's population has grown slower than the state average since the 2000s. This is due to California's growth becoming concentrated in the northern part of the state as result of a stronger, tech-oriented economy in the Bay Area and an emerging Greater Sacramento region. Southern California consists of one Combined Statistical Area , eight Metropolitan Statistical Areas , one international metropolitan area , and multiple metropolitan divisions. The region

704-473: A population of approximately 4 million, Los Angeles is the most populous city in California and the second most populous in the United States. South of Los Angeles and with a population of approximately 1.4 million is San Diego, the second most populous city in the state and the eighth most populous in the nation. The counties of Los Angeles , San Diego , Orange , Riverside , and San Bernardino are

792-587: A possible driver for the deformation of the Basin and Range , separation of the Baja California peninsula , and rotation of the Transverse Range . The main southern section of the San Andreas Fault proper has only existed for about 5 million years. The first known incarnation of the southern part of the fault was Clemens Well-Fenner- San Francisquito fault zone around 22–13 Ma. This system added

880-769: A whole enacted the Alquist Priolo Special Studies Zone Act in the wake of the 1971 San Fernando earthquake . The act prohibits new construction of residential buildings closer than 50 feet (15 m) from a surface rupturing active fault zone. In addition, the act improved safety by requiring new structures (both residential and commercial) to be seismically retrofitted. It also required existing infrastructure to comply. Since 1972, numerous large magnitude earthquakes have struck Southern California with little widespread damage in part due to act. However, exceptions can be noted for epicenters that lie directly on top of densely populated regions such as

968-804: Is a geographic and cultural region that generally comprises the southern portion of the U.S. state of California . It includes the Los Angeles metropolitan area (the second most populous urban agglomeration in the United States ) as well as the Inland Empire (another large metropolitan area). The region generally contains ten of California's 58 counties: Los Angeles , San Diego , Orange , Riverside , San Bernardino , Kern , Ventura , Santa Barbara , San Luis Obispo , and Imperial counties. Although geographically smaller than Northern California in land area, Southern California has

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1056-399: Is a stub . You can help Misplaced Pages by expanding it . This San Luis Obispo County, California -related article is a stub . You can help Misplaced Pages by expanding it . San Andreas Fault 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

1144-499: Is a combined effort from experts in the physical sciences, social sciences, and engineering both in the public and private sectors- ranging from urban planners to economists/business professionals. Not only does this study aim to estimate the impacts of the event, but aims to estimate the years of rebuilding and funding needed to recover communities from a potential disaster such as the HayWired Scenario. The first volume of

1232-502: Is also home to a large surf and skateboard culture. Companies such as Vans , Volcom , Quiksilver , No Fear , Stüssy , RVCA , and Body Glove are all headquartered there. Skateboarder Tony Hawk ; surfers Rob Machado , Timmy Curran , Bobby Martinez , Pat O'Connell , Dane Reynolds , and Chris Ward live in Southern California. Some of the most famous surf locations are in Southern California as well, including Trestles , Rincon , The Wedge , Huntington Beach , and Malibu . Some of

1320-513: Is also known for its mountain resort communities, such as Big Bear Lake , Lake Arrowhead , and Wrightwood , and their ski resorts, like Bear Mountain , Snow Summit , Snow Valley Mountain Resort , and Mountain High . The inland desert city of Palm Springs is also popular. Southern California is generally considered the area of California south of the latitude 35°45', approximately one-third of

1408-687: Is an important government, arts and entertainment, and retail district. Downtown San Diego is the CBD of San Diego, though the city is filled with business districts. These include Carmel Valley , Del Mar Heights , Mission Valley , Rancho Bernardo , Sorrento Mesa , and University City . Most of these districts are located in Northern San Diego and some within North County regions. Los Angeles Orange County Riverside & San Bernardino San Diego Southern California

1496-410: Is home to Los Angeles International Airport , the second-busiest airport in the United States by passenger volume (see World's busiest airports by passenger traffic ) and the third-busiest by international passenger volume (see Busiest airports in the United States by international passenger traffic ); San Diego International Airport , the busiest single-runway airport in the world; Van Nuys Airport ,

1584-568: Is home to two extended metropolitan areas that exceed five million in population. These are the Greater Los Angeles Area at 17,786,419, and San Diego–Tijuana at 5,105,768. Of these metropolitan areas, the Los Angeles-Long Beach-Santa Ana metropolitan area , Riverside-San Bernardino-Ontario metropolitan area , and Oxnard-Thousand Oaks-Ventura metropolitan area form Greater Los Angeles; while

1672-401: Is low to moderate depending on the area. Rain is infrequent, but is often heavy when it does occur, making flash floods an aspect of living in Southern California. This climatic pattern was alluded to in the hit song " It Never Rains (In Southern California) ". While snow is very rare in lower elevations, mountains above 5,000 feet (1,500 m) receive plentiful snowfall in the winter. Since

1760-554: Is not clear. Several hypotheses have been offered and research is ongoing. One hypothesis – which gained interest following the Landers earthquake in 1992 – suggests the plate boundary may be shifting eastward away from the San Andreas towards Walker Lane. Assuming the plate boundary does not change as hypothesized, projected motion indicates that the landmass west of the San Andreas Fault, including Los Angeles, will eventually slide past San Francisco, then continue northwestward toward

1848-566: Is the approximate location of the epicenter of the 1906 San Francisco earthquake . The fault returns onshore at Bolinas Lagoon just north of Stinson Beach in Marin County . It returns underwater through the linear trough of Tomales Bay which separates the Point Reyes Peninsula from the mainland, runs just east of Bodega Head through Bodega Bay and back underwater, returning onshore at Fort Ross . (In this region around

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1936-420: The 1994 Northridge earthquake ) occurs about once every 6.7 years statewide. The same report also estimated there is a 7% probability that an earthquake of magnitude 8.0 or greater will occur in the next 30 years somewhere along the San Andreas Fault. A different USGS study in 2008 tried to assess the physical, social and economic consequences of a major earthquake in southern California. That study predicted that

2024-681: The Aleutian Trench , over a period of perhaps twenty million years. 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 plate and the Farallon plate (which is now mostly subducted, with remnants including the Juan de Fuca plate , Rivera plate , Cocos plate , and the Nazca plate ) was beginning to reach

2112-605: The El Centro metropolitan area and San Diego-Carlsbad-San Marcos metropolitan area form the Southern Border Region . North of Greater Los Angeles are the Santa Barbara , San Luis Obispo , and Bakersfield metropolitan areas. Los Angeles (with a population of approximately 3.9 million people) and San Diego (at nearly 1.4 million people) are the two largest cities in all of California, and are among

2200-650: The Los Angeles metropolitan area ( Los Angeles and Orange counties, with 13.3 million people), the Inland Empire ( Riverside and San Bernardino counties, including the Coachella Valley cities, with 4.3 million people), and the Oxnard–Thousand Oaks–Ventura metropolitan area (0.8 million people). In addition, Southern California contains the San Diego metropolitan area with 3.3 million people, Bakersfield metro area with 0.9 million, and

2288-717: The Mojave Desert shares a border with Nevada to the northeast. Southern California's southern border with Baja California is part of the Mexico–United States border . Southern California encompasses eight metropolitan areas (MSAs), three of which together form the Greater Los Angeles Combined Statistical Area (CSA) with over 18 million people, the second-biggest CSA after the New York CSA . These three MSAs are

2376-760: The Newport–Inglewood-Rose Canyon Fault (located adjacent to SoFi Stadium and responsible for Signal Hill ), the Elsinore Fault (created Lake Elsinore ), the Garlock Fault (which marks boundary between of the Sierra Nevada and the Mojave Desert ), and the Hollywood fault (which is within feet of Capitol Records and is roughly parallel to Hollywood Boulevard ). The United States Geological Survey (USGS) has released

2464-524: The Salton Sea . Here, the plate motion is being reorganized from right-lateral to divergent . In this region (known as the Salton Trough ), the plate boundary has been rifting and pulling apart, creating a new mid-ocean ridge that is an extension of the Gulf of California . Sediment deposited by the Colorado River is preventing the trough from being filled in with sea water from the gulf. The fault

2552-779: The San Diego metropolitan area as they do with the Inland Empire . To the east, the United States Census Bureau considers the San Bernardino and Riverside County areas, Riverside-San Bernardino area as a separate metropolitan area from Los Angeles County. Newly developed exurbs formed in the Antelope Valley , north of Los Angeles, the Victor Valley , and the Coachella Valley with the Imperial Valley . Also, population growth

2640-492: The San Fernando Valley . The area of Santa Monica and Venice (and perhaps some of Culver City) is informally referred to as "Silicon Beach" because of the concentration of financial and marketing technology-centric firms located in the region. The San Bernardino-Riverside Area maintains the business districts of Downtown San Bernardino , Hospitality Business/Financial Centre , University District which are in

2728-573: The San Francisco Bay Area several significant "sister faults" run more-or-less parallel, and each of these can create significantly destructive earthquakes.) From Fort Ross, the northern segment continues overland, forming in part a linear valley through which the Gualala River flows. It goes back offshore at Point Arena . After that, it runs underwater along the coast until it nears Cape Mendocino , where it begins to bend to

Hosgri Fault - Misplaced Pages Continue

2816-473: The San Gabriel Fault as a primary focus of movement between 10–5 Ma. Currently, it is believed that the modern San Andreas will eventually transfer its motion toward a fault within the eastern California shear zone . This complicated evolution, especially along the southern segment, is mostly caused by either the "Big Bend" and/or a difference in the motion vector between the plates and the trend of

2904-699: The San Gabriel Mountains . These mountains are a result of movement along the San Andreas Fault and are commonly called the Transverse Range. In Palmdale , a portion of the fault is easily examined at a roadcut for the Antelope Valley Freeway . The fault continues northwest alongside the Elizabeth Lake Road to the town of Elizabeth Lake . As it passes the towns of Gorman , Tejon Pass and Frazier Park ,

2992-480: The Santa Barbara , San Luis Obispo , and El Centro (Imperial County) metropolitan areas. The Southern California Megaregion (or megalopolis ) is larger still, extending northeast into Las Vegas , Nevada and south across the Mexican border into Tijuana . Within Southern California are two major cities, Los Angeles and San Diego , as well as three of the country's largest metropolitan areas . With

3080-652: The Santa Cruz Mountains (the location of the Loma Prieta earthquake in 1989). Studies of the relative motions of the Pacific and North American plates have shown that only about 75 percent of the motion can be accounted for in the movements of the San Andreas and its various branch faults. The rest of the motion has been found in an area east of the Sierra Nevada mountains called the Walker Lane or Eastern California Shear Zone. The reason for this

3168-526: The Transverse and Peninsular Ranges with their peaks, and into the large and small interior valleys, to the vast deserts of California . Note: Plate boundary faults are indicated with a (#) symbol. Each year, Southern California has about 10,000 earthquakes. Nearly all of them are too small to be felt. Only several hundred have been greater than magnitude (M w  ) 3.0, and only about 15–20 have been greater than M w   4.0. California as

3256-526: The U.S. Geological Survey (USGS) have made variable predictions as to the risk of future seismic events. The ability to predict major earthquakes with sufficient precision to warrant increased precautions has remained elusive. The U.S. Geological Survey's most recent forecast, known as UCERF3 (Uniform California Earthquake Rupture Forecast 3), released in November 2013, estimated that an earthquake of magnitude 6.7 M or greater (i.e. equal to or greater than

3344-403: The entertainment industry . Other industries include software, automotive, aerospace, finance, biomedical, ports and regional logistics. The region was a leader in the housing bubble from 2001 to 2007, and has been heavily impacted by the housing crash. Since the 1920s, motion pictures, petroleum, and aircraft manufacturing have been major industries. In one of the richest agricultural regions in

3432-522: The tectonic boundary between the Pacific plate and the North American plate . Traditionally, for scientific purposes, the fault has been classified into three main segments (northern, central, and southern), each with different characteristics and a different degree of earthquake risk. The average slip rate along the entire fault ranges from 20 to 35 mm (0.79 to 1.38 in) per year. In

3520-587: The California economy within the first 6 months post-recovery from the event through estimates of "utility outages, property damages, and supply chain disruptions resulting in an estimated $ 44 billion of gross state product (GSP) losses, or translated at 4% of the California economy"(Wein et al.). This study also projects the recovery of jobs lost in highly impacted areas, such as Alameda County, could take up to 10 years to fully recover job losses and possible economic recession. Trajectories for economic recovery are improved by reconstruction but also delayed with impacts to

3608-661: The HayWired Scenario study was released in 2017, with consistent continuations and contributions by engineers. This continuation was published in the second volume, Engineering Implications, in 2018. As of the 2021 Fact sheet update, there are several estimates on damages ranging from the approximate people affected at home, work, effects of lifeline infrastructures such as telecommunications, and more. This group of scientists have worked together to create estimates of how hazards such as liquefaction, landslides, and fire ignition will impact access to utilities, transportation, and general emergency services. This study goes into detail about

Hosgri Fault - Misplaced Pages Continue

3696-546: The Los Angeles Area are the major business districts of Downtown Pasadena , Downtown Burbank , Downtown Santa Monica , Downtown Glendale and Downtown Long Beach . Los Angeles proper has many business districts, such as Downtown LA and those lining Wilshire Boulevard , including Mid-Wilshire , the Miracle Mile , Downtown Beverly Hills , and Westwood ; others include Century City and Warner Center in

3784-399: The M w   6.7 1994 Northridge Earthquake and, to a lesser extent, the smaller M w   5.5 2008 Chino Hills earthquake . The Northridge earthquake occurred on a blind-thrust fault directly underneath the San Fernando Valley , which until the earthquake was previously undiscovered. Seismic retrofitting of existing and new construction is aimed to prevent damage and save lives in

3872-463: The San Andreas fault has reached a sufficient stress level for an earthquake of magnitude greater than 7.0 on the moment magnitude scale to occur. This study also found that the risk of a large earthquake may be increasing more rapidly than scientists had previously believed. Moreover, the risk is currently concentrated on the southern section of the fault, i.e. the region around Los Angeles, because strong earthquakes have occurred relatively recently on

3960-456: The Southern California desert system. Because of the barrier formed by the Tehachapi and Sierra Nevada ranges, cartographer George Wheeler observed in 1876 that Northern California was better connected to Oregon and Nevada than it was to Southern California. Following the acquisition of the territory of California by the United States, several pro-slavery politicians attempted to arrange

4048-493: The U.S., cattle and citrus were major industries until farmlands were turned into suburbs. Although military spending cutbacks have had an impact, aerospace continues to be a major factor. Southern California is home to many major business districts. Central business districts (CBD) include Downtown Los Angeles , Downtown Riverside , Downtown San Bernardino , downtown San Diego , and the South Coast Metro . Within

4136-578: The abnormally long period of time since the last major earthquake in the region since the lake has dried up. The San Andreas Fault System has been the subject of a flood of studies. In particular, scientific research performed during the last 23 years has given rise to about 3,400 publications. A study published in 2006 in the journal Nature by Yuri Fialko, an associate professor at the Cecil H. and Ida M. Green Institute of Geophysics and Planetary Physics at Scripps Institution of Oceanography , found that

4224-432: The aftermath of a major quake, but it cannot guarantee that buildings will be unscathed if the epicenter is relatively close by. The 1994 Northridge earthquake was particularly destructive, causing a substantial number of deaths, injuries, and structural collapses. The quake caused the most property damage of any earthquake in U.S. history at an estimated $ 20 billion. Many Southern California faults are able to produce

4312-555: The centers of their respective metropolitan areas, composed of numerous smaller cities and communities. The urban area is also host to an international San Diego–Tijuana metropolitan region, created by the urban area spilling over into Baja California . The main barrier to urbanization along the Interstate 5 corridor is Camp Pendleton . The cities and communities along Interstate 15 and Interstate 215 are so interrelated that Temecula and Murrieta have as much connection with

4400-1194: The central ( 1857 ) and northern ( 1906 ) segments of the fault, while the southern section has not seen any similar rupture for at least 300 years. According to this study, a major earthquake on that southern section of the San Andreas fault would result in major damage to the Palm Springs – Indio metropolitan area and other cities in San Bernardino , Riverside and Imperial counties in California, and Mexicali Municipality in Baja California . It would be strongly felt (and potentially cause significant damage) throughout much of Southern California , including densely populated areas of Los Angeles County , Ventura County , Orange County , San Diego County , Ensenada Municipality and Tijuana Municipality , Baja California, San Luis Rio Colorado in Sonora and Yuma, Arizona . Older buildings would be especially prone to damage or collapse, as would buildings built on unconsolidated gravel or in coastal areas where water tables are high (and thus subject to soil liquefaction ). Of

4488-612: The cities of San Bernardino and Riverside. In Orange County, has highly developed suburban business centers (also known as edge cities ) including the Anaheim–Santa Ana edge city along I-5; and another, the South Coast Plaza–John Wayne Airport edge city that stretches from the South Coast Metro to the Irvine Business Complex ; Newport Center ; and Irvine Spectrum . Downtown Santa Ana

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4576-523: The construction industry. A 2008 paper, studying past earthquakes along the Pacific coastal zone, found a correlation in time between seismic events on the northern San Andreas Fault and the southern part of the Cascadia subduction zone (which stretches from Vancouver Island to Northern California). Scientists believe quakes on the Cascadia subduction zone may have triggered most of the major quakes on

4664-594: The division of Alta California at 36 degrees, 30 minutes, the line of the Missouri Compromise . Instead, the passing of the Compromise of 1850 enabled California to be admitted to the Union as a free state , preventing the southern half of California from becoming its own separate slave state . Subsequently, Californians (dissatisfied with inequitable taxes and land laws) and pro-slavery Southerners in

4752-594: The eastern side of the fault. The effect is expressed as the Coast Ranges. The northwest movement of the Pacific plate is also creating significant compressional forces which are especially pronounced where the North American plate has forced the San Andreas to jog westward. This has led to the formation of the Transverse Ranges in Southern California, and to a lesser but still significant extent,

4840-515: The fault and its surrounding branches. 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 that the San Andreas Fault stretched southward into southern California after reviewing the effects of the 1906 San Francisco earthquake . Large-scale (hundreds of miles) lateral movement along

4928-560: The fault begins to bend northward, forming the "Big Bend". This restraining bend is thought to be where the fault locks up in Southern California , with an earthquake-recurrence interval of roughly 140–160 years. Northwest of Frazier Park, the fault runs through the Carrizo Plain , a long, treeless plain where much of the fault is plainly visible. The Elkhorn Scarp defines the fault trace along much of its length within

5016-540: The fault from 2004 to 2007. The aim was to collect core samples and make direct geophysical and geochemical observations to better understand fault behavior at depth. 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 Professor Lawson in 1895, then offshore at Daly City near Mussel Rock . This

5104-452: The fault he previously discovered. He concluded that the fault must have been the origin of the earthquake. This line ran through San Andreas Lake , a sag pond . The lake was created from an extensional step over in the fault, which created a natural depression where water could settle. A common misconception is that Lawson named the fault after this lake. However, according to some of his reports from 1895 and 1908, he actually named it after

5192-632: The fault was first proposed in a 1953 paper by geologists Mason Hill and Thomas Dibblee . This idea, which was considered radical at the time, has since been vindicated by modern plate tectonics . Seismologists discovered that the San Andreas Fault near Parkfield in central California consistently produces a magnitude 6.0 earthquake approximately once every 22 years. Following recorded seismic events in 1857, 1881, 1901, 1922, 1934, and 1966, scientists predicted that another earthquake should occur in Parkfield in 1993. It eventually occurred in 2004 . Due to

5280-429: The first decade of the 21st century, droughts and wildfires have increased in frequency as a result of climate change . Southern California consists of one of the more varied collections of geologic, topographic, and natural ecosystem landscapes in a diversity outnumbering other major regions in the state and country. The region spans from Pacific Ocean islands , shorelines , beaches, and coastal plains , through

5368-633: The five most populous in the state, and are among the top 15 most populous counties in the United States. The motion picture , television and music industry are centered in the Los Angeles area in Southern California. Hollywood , a district of Los Angeles, gives its name to the American motion picture industry, which is synonymous with the neighborhood name. Headquartered in Southern California are The Walt Disney Company (which owns ABC ), Sony Pictures , Universal Pictures , MGM , Paramount Pictures , and Warner Bros . Universal, Warner Bros., and Sony also run major record companies. Southern California

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5456-474: The frequency of predictable activity, Parkfield has become one of the most important areas in the world for large earthquake research. In 2004, work began just north of Parkfield on the San Andreas Fault Observatory at Depth (SAFOD). The goal of SAFOD is to drill a hole nearly 3 kilometres (1.9 mi) into the Earth's crust and into the San Andreas Fault. An array of sensors will be installed to record earthquakes that happen near this area. A 2023 study found

5544-433: The geological impacts/effects of the event, but also the societal impacts such as property damage, economic rebuilding, and aims at estimating damages if cities increased risk-reduction. It was developed for preparedness geared towards Bay Area residents and as a warning with an attempt to encourage local policy makers to create infrastructure and protections that would further risk reduction and resilience-building. This study

5632-444: The lightly populated "cow counties" of Southern California attempted three times in the 1850s to achieve a separate statehood or territorial status separate from Northern California . The last attempt, the Pico Act of 1859, was passed by the California State Legislature and signed by State Governor John B. Weller . It was approved overwhelmingly by nearly 75 percent of voters to form the proposed Territory of Colorado . This territory

5720-435: The more urban region) that have been left undeveloped. It is the third most populated megalopolis in the United States, after the Great Lakes megalopolis and the Northeast megalopolis . Much of Southern California is famous for its large, spread-out, suburban communities and use of automobiles and highways. The dominant areas are Los Angeles, Orange County , San Diego , and Riverside – San Bernardino , each of which are

5808-448: The north, the fault terminates offshore near Eureka, California , at the Mendocino triple junction , where three tectonic plates meet. The Cascadia subduction zone intersects the San Andreas fault at the Mendocino triple junction. It has been hypothesized that a major earthquake along the Cascadia subduction zone could trigger a rupture along the San Andreas Fault. In the south, the fault terminates near Bombay Beach, California , in

5896-547: The northern San Andreas within the past 3,000 years. The evidence also shows the rupture direction going from north to south in each of these time-correlated events. However the 1906 San Francisco earthquake seems to have been the exception to this correlation because the plate movement was mostly from south to north and it was not preceded by a major quake in the Cascadia zone. The San Andreas Fault has had some notable earthquakes in historic times: Southern California Southern California (commonly shortened to SoCal )

5984-425: The nuclear Diablo Canyon Power Plant . In fact, the fault lies only 2 + 1 ⁄ 2 miles offshore from the nuclear power plant . More recently in 2008, yet another even closer fault was discovered, the Shoreline Fault 1 mile from the NPP. 35°07′N 119°39′W  /  35.117°N 119.650°W  / 35.117; -119.650 This article about a specific United States geological feature

6072-485: The plain. The southern segment, which stretches from Parkfield in Monterey County all the way to the Salton Sea , is capable of an 8.1-magnitude earthquake. At its closest, this fault passes about 35 miles (56 km) to the northeast of Los Angeles. Such a large earthquake on this southern segment would kill thousands of people in Los Angeles, San Bernardino, Riverside, and surrounding areas, and cause hundreds of billions of dollars in damage. The Pacific plate , to

6160-422: The sole county to vote for the GOP, with Orange County having been Democrat since 2012. Southern California is one of the largest economies in the United States. It is dominated by, and heavily dependent upon, the abundance of petroleum, as opposed to other regions where automobiles are not nearly as dominant, due to the vast majority of transport that runs on this fuel. Southern California is famous for tourism and

6248-406: The southern section of the San Andreas (in the Palm Springs region, which has not ruptured in ~400 years), the entire Southern California portion of the San Andreas Fault is ready to produce a powerful earthquake in the near future. Notable faults capable of large magnitude events include the San Jacinto Fault (a splay of the San Andreas that runs directly under the I-10 & I-215 interchange),

6336-526: The specific populations to be hardest impacted by a potential earthquake of a 7.0 magnitude, specifically in the San Francisco Bay Area. This includes intensified hardships for those with low-income, racially and culturally-diverse populations, and people with literacy hardships that would significantly "increase their risk of displacement and add to recovery challenges" (Wein et al.). In addition to societal and landscape impacts, this study looks at potential business interruptions. This portion estimates impacts to

6424-470: The state, formed by the northern boundaries of San Luis Obispo , Kern , and San Bernardino counties, which are not exactly a straight line. Another definition for Southern California uses Point Conception and the Tehachapi Mountains as the northern geographical barriers, especially when defining California's bioregions . In this definition, Owens Valley and Death Valley are part of

6512-472: The study, Fialko stated: All these data suggest that the fault is ready for the next big earthquake but exactly when the triggering will happen and when the earthquake will occur we cannot tell. It could be tomorrow or it could be 10 years or more from now. Nevertheless, in the 18 years since that publication there has not been a substantial quake in the Los Angeles area, and two major reports issued by

6600-500: The subduction zone off the western coast of North America. As the relative motion between the Pacific and North American plates was different from the relative motion between the Farallon and North American plates, the spreading ridge began to be "subducted", creating a new relative motion and a new style of deformation along the plate boundaries. These geological features are what are chiefly seen along San Andreas Fault. It also includes

6688-533: The surrounding San Andreas Valley. Following the 1906 San Francisco earthquake, Lawson also concluded that the fault extended all the way into Southern California . In 1953, geologist Thomas Dibblee concluded that hundreds of miles of lateral movement could occur along the fault. A National Science Foundation funded project called the San Andreas Fault Observatory at Depth (SAFOD) near Parkfield, California , involved drilling through

6776-417: The top eight largest cities in the United States. In Southern California, there are also 14 cities with more than 200,000 residents and 48 cities over 100,000 residents. Many of Southern California's most developed cities lie along or in close proximity to the coast, with the exception of San Bernardino and Riverside. Southern California has drifted left since 2004, and is solidly Democrat. Kern County remains

6864-420: 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 under the influence of plate tectonics . The rate of slippage averages about 33 to 37 millimeters (1.3 to 1.5 in) a year across California. The southwestward motion of the North American plate towards the Pacific is creating compressional forces along

6952-479: The west, terminating at the Mendocino triple junction . The central segment of the San Andreas Fault runs in a northwestern direction from Parkfield to Hollister . While the southern section of the fault and the parts through Parkfield experience earthquakes, the rest of the central section of the fault exhibits a phenomenon called aseismic creep , where the fault slips continuously without causing earthquakes. It

7040-429: The world's busiest general aviation airport; major commercial airports at San Bernardino , Orange County , Bakersfield , Ontario , Burbank , and Long Beach ; and numerous smaller commercial and general aviation airports. Six of the seven lines of the commuter rail system, Metrolink , run out of Downtown Los Angeles, connecting Los Angeles, Ventura , San Bernardino, Riverside, Orange, and San Diego counties with

7128-435: The world's largest action sports events, including the X Games , Boost Mobile Pro , and the U.S. Open of Surfing , are held in Southern California. The region is also important to the world of yachting with premier events including the annual Transpacific Yacht Race , or Transpac , from Los Angeles to Hawaii. San Diego Yacht Club hosted the three America's Cup races from 1988 to 1995. The first modern-era triathlon

7216-425: Was first identified in 1895 by Professor Andrew Lawson of UC Berkeley . In the wake of the 1906 San Francisco earthquake , Lawson was tasked with deciphering the origin of the earthquake. He began by surveying and mapping offsets (such as fences or roads that had been sliced in half) along surface ruptures. When the location of these offsets were plotted on a map, he noted that they made a near perfect line on top of

7304-528: Was formed by a transform boundary. The southern segment (also known as the Mojave segment) begins near Bombay Beach, California . Box Canyon, near the Salton Sea , contains upturned strata associated with that section of the fault. The fault then runs along the southern base of the San Bernardino Mountains , crosses through Cajon Pass and continues northwest along the northern base of

7392-528: Was grouped with other counties of the San Joaquin Valley , California's central agricultural valley. Southern California consists of a heavily developed urban environment, home to some of the largest urban areas in the state, along with the Deserts of California (part of which was even proposed to become a new county due to cultural, economic and geographic differences relative to the rest of

7480-590: Was held in San Diego's Mission Bay in 1974. Since then, Southern California, and San Diego in particular, have become a mecca for triathlon and multi-sport racing, products, and culture. Southern California has multiple sports franchises and networks, such as Fox Sports Net . Many of these locals and tourists frequent the Southern California coast for its beaches. Some of Southern California's most popular beaches are Malibu , Laguna Beach , La Jolla , Manhattan Beach , and Hermosa Beach . Southern California

7568-546: Was high in the Bakersfield-Kern County , Santa Maria , and San Luis Obispo areas. Most of Southern California has a Mediterranean -like climate, with warm and dry summers, mild and wet winters, where cool weather and freezing temperatures are rare. Southern California contains other types of climates, including semi-arid , desert and mountain , with infrequent rain and many sunny days. Summers are hot or warm, and dry, while winters are mild, and rainfall

7656-698: Was the name of a proposed new state which failed to get on the 2018 California ballot. The ballot measure proposed splitting the existing state into three parts. In December 2020, during the COVID-19 pandemic , the state government led by Governor Gavin Newsom divided the state into five regions for the purpose of issuing stay-at-home orders. The Southern California region consisted of the following counties: Imperial , Inyo , Los Angeles , Mono , Orange , Riverside , San Bernardino , San Diego , San Luis Obispo , Santa Barbara , and Ventura . However, Kern County

7744-773: Was to include a portion of the much larger Tulare County and all of San Luis Obispo County . The proposal was sent to Washington, D.C. , with a strong advocate in Senator Milton Latham . However, the secession crisis following the election of Abraham Lincoln in 1860 and the subsequent American Civil War led to the proposal never coming to a vote. In 1900, the Los Angeles Times defined Southern California as including "the seven counties of Los Angeles, San Bernardino, Orange, Riverside, San Diego, Ventura, and Santa Barbara." This definition left out San Luis Obispo and Kern counties. Southern California

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