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9.4: Central Coast

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    The Central Coast is an area of California, roughly spanning the coastal region between Point Mugu and Monterey Bay and is part of the Central Coast American Viticultural Area, which is often referred to as the ’Wine Country’ of the state. It lies northwest of Los Angeles County and south of San Mateo and Santa Clara counties, and includes the rugged, undeveloped stretch of coastline known as Big Sur. From south to north, there are six counties that make up the Central Coast: Ventura, Santa Barbara, San Luis Obispo, Monterey, San Benito, and Santa Cruz.

    Map of California's Central Coast.
    Figure 9.5: Location of the Central Coast in California. Map of the Central Coast region of California by Wikimedia User Cristiano Tomás is used under a CC BY-SA 4.0 license.

    Physical Geography

    Geographically, the actual midpoint of the California coast lies north of Santa Cruz, near Año Nuevo State Park in San Mateo County. Neither the popular use of the term Central Coast nor that of the California North Coast include the San Francisco Peninsula counties of San Mateo and San Francisco.

    The region is known primarily for agriculture and tourism. Major crops include wine grapes, lettuce, strawberries, and artichokes. The Salinas Valley is one of the most fertile farming regions in the United States. Tourist attractions include Cannery Row in Monterey, the Monterey Bay Aquarium, the theatres, galleries and white sand beaches of Carmel-by-the-Sea, the golf courses of Pebble Beach and the Monterey Peninsula, the rugged coastline of Big Sur and Hearst Castle in San Simeon. Further south is Morro Rock and the port city of Morro Bay, which is adjacent to college town San Luis Obispo. The Santa Ynez Valley is home to the Central Coast Film Society, which celebrates filmmakers, cinema and media arts that are from the region, also known as "Hollywood's Backyard."

    University of California campuses are found in Santa Barbara and Santa Cruz, near the south and north edges of the region respectively. California State University, Monterey Bay, founded in 1994, uses facilities donated when Fort Ord was converted from military to civilian uses. California Polytechnic State University, in San Luis Obispo, was founded in 1901. California State University Channel Islands opened in Camarillo in 2002, as the 23rd campus in the California State University system.

    Field Trip: Morro Bay & Morro Rock

    Let’s head on field trip to Morro Bay and Morro Rock! Either scan the QR code or visit this link to see Professor Patrich explore Morro Bay in San Louis Obispo, California. (Video length: 6min).

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    Physical Geology - Case Study – Santa Barbara

    The city of Santa Barbara is situated on a coastal plain between the Santa Ynez Mountains and the sea. This coastal plain consists of a complex array of Holocene and Pleistocene alluvial and colluvial deposits, marine terraces, debris flows, and estuarine deposits. Soils are mostly well drained brown fine sandy loam of the Milpitas series. Rapid geologic uplift is characteristic of the entire region, as evidenced by the coastal bluffs and narrow beaches that are present along most of the coastline.

    Downtown Santa Barbara occupies a floodplain between two major geologic faults, the Mission Ridge Fault Zone to the north and the Mesa Fault to the south. The Mission Ridge Fault Zone runs along the range of hills known locally as the "Riviera", and the Mesa Fault defines the northern boundary of the band of hills called the "Mesa". These two faults converge near the Five Points Shopping Center at Los Positas and State Streets. Neither is well-exposed, with their locations being inferred from topography, springs, seeps, and well logs. The Mesa Fault continues southeast offshore into the Santa Barbara Channel; the portion of the fault offshore is believed to have been responsible for the destructive earthquake of 1925. The Mission Ridge Fault trends east–west, being named the More Ranch Fault west of Santa Barbara, and forms the northern boundary of the uplands which include Isla Vista, More Mesa, and the Hope Ranch Hills.

    Mission Santa Barbara, after the Santa Barbara earthquake, 29 June 1925
    Figure 9.6: Mission Santa Barbra, After the Santa Barbra Earthquake in 1925. Mission Santa Barbara 1925 hosted on Wikimedia Commons in the public domain.

    Three major sedimentary bedrock units underlie the coastal plain: the Monterey Formation, the Sisquoc Formation, and the Santa Barbara Formation. The Santa Barbara Formation is one of the main units in the aquifer underlying the city. Its coarse-grained freshwater-bearing portion, much of which is below sea level, is protected from seawater intrusion by the More Ranch Fault, which has shielded it by uplifting less-permeable rocks between it and the sea. Most water wells in the Santa Barbara-Goleta area pull from this geologic unit.

    The Santa Ynez Mountains to the north of the city consist of multiple layers of sandstone and conglomerate units dating from the Jurassic Age to the present, uplifted rapidly since the Pliocene, upended, and in some areas completely overturned. Rapid uplift has given these mountains their craggy, scenic character, and numerous landslides and debris flows, which form some of the urban and suburban lowland area, are testament to their geologically active nature.

    Field Trip: Pillow Basalts in San Louis Obispote

    Let’s head on field trip to Avila Beach! Either scan the QR code or visit this link to see Professor Patrich explore pillow Basalts in San Louis Obispo, California. (Video length: 4min).

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    Cultural Geography - Santa Barbara Architecture

    The first Monterey-style adobe in California was built on State Street of Santa Barbara by the wealthy merchant Alpheus Thompson. The dominant architectural themes of Santa Barbara are the Mediterranean Revival, Spanish Colonial Revival, and the related Mission Revival style, encouraged through design guidelines adopted by city leaders after the 1925 earthquake destroyed much of the downtown commercial district. Residential architectural styles in Santa Barbara reflect the era of their construction. Many late-1800s Victorian homes remain downtown and in the "Upper East" neighborhood. California bungalows are common, built in the early decades of the 20th century. Spanish Colonial Revival-style homes built after 1925 are common all over the city, especially in newer upscale residential areas like Montecito and Hope Ranch. Notable modernist and contemporary homes can be found as well.

    Physical Geology - Case Study – Ventura County

    Ventura county is on a tectonically active plate, since most of Coastal California is near the boundaries between the Pacific and North American Plates. The county of Ventura is made up of 10 incorporated cities: Camarillo, Fillmore, Moorpark, Ojai, Oxnard, Port Hueneme, Santa Paula, Simi Valley, Thousand Oaks, and San Buenaventura.

    The San Andreas Fault, which demarcates this boundary, is about 40 miles away. One active fault that transverses the city of Oxnard is the Oak Ridge Fault, which straddles the Santa Clara River Valley westward from the Santa Susana Mountains, crosses the Oxnard Plain through Oxnard, and extends into the Santa Barbara Channel. The coastline is subject to inundation by a tsunami up to 23 feet in height. The San Andreas has proven to be a significant contributor to seismic activity in the Oxnard region and beyond. The 6.7 Mw Northridge earthquake that occurred on January 17, 1994, is believed to have occurred in the Santa Clarita extension of the Oak Ridge Fault. Landslides and ridge-top shattering resulting from the Northridge earthquake were observed above Moorpark, a city 19.6 mi (31.5 km) east of Oxnard

    Running through the middle of the county is the Ventura Oil Field, which is a large and currently productive oil field in the hills just north of the city center of Ventura. The Ventura field, the large-scale structural feature responsible for petroleum accumulation is the Ventura Anticline, an east-west trending geologic structure 16 miles (26 km) long, visible in the numerous rock outcrops in the rugged topography of the area. This anticline dips steeply on both sides, with the dip angle ranging from 30 to 60 degrees, resulting in a series of rock beds resembling a long house with a gabled roof, under which oil and gas collect in abundance.

    Map of the Ventura Oil Field.
    Figure 9.7: Map of the Ventura Oil Field. VenturaDetail by User:Antandrus is used under a CC BY-SA 3.0 license.

    Within this feature, the primary petroleum-bearing unit is the Pico Formation, a sedimentary unit of turbidite sands of high porosity (16 to 20 percent). Additionally, oil is found in the underlying Santa Margarita Formation. Eight different oil-bearing zones have been identified by number, 1st through 8th based on depth, with the 2nd zone the first to be discovered, in March 1919 by the Shell Oil Company. The pools range in depth from 3,680 feet (1,120 m) to over 12,000 feet (3,700 m), although depth within each pool varies greatly; the discovery well into the 2nd zone, which has an average depth of 5,180 feet (1,580 m), had a total depth of only 3,500 feet (1,100 m).

    The underlying Monterey Formation is presumed to be the source of the oil accumulations in the Ventura field, as well as the other two fields in the same geologic trend. The Monterey Formation is rich in organic matter, averaging 3-5 percent but reaching 23 percent in some areas. Oil likely migrated upwards during the late Pliocene, becoming trapped in the folds and structural traps of the higher rocks of the anticline which form an impermeable cap. Some of the oil-bearing zones, such as the 4th and 5th, are capped by the Barnard Fault, which provides an additional structural trap. Even with the impermeable caps and structural traps, there are enough breaks in the structure for significant natural tar seeps to occur; indeed, the entire region is riddled with natural seeps, and tar was used by the native Chumash peoples as a sealant for their watercraft.

    Cultural Geography - Case Study – Ventura County

    Pre-Colonial Period

    Ventura County was historically inhabited by the Chumash people, who also settled much of Santa Barbara and San Luis Obispo Counties, with their presence dating back 10,000–12,000 years. The Chumash were hunter-gatherers, fishermen, and traders with the Mojave, Yokuts, and Tongva Indians. The Chumash are also known for their rock paintings and for their great basketry. The plank canoe, called a tomol in Chumash, was important to their way of life. Canoe launching points on the mainland for trade with the Chumash of the Channel Islands were located at the mouth of the Ventura River, Mugu Lagoon and Point Hueneme. This has led to speculations among archeologists of whether the Chumash could have had a pre-historic contact with Polynesians. According to diachronic linguistics, certain words such as tomolo’o (canoe) could be related to Polynesian languages. The dialect of the Chumash language that was spoken in Ventura County was Ventureño.

    Map of Ventura County with phyusciographical place names.
    Figure 9.8: Physiographic Map of Ventura County with Place Names. Ventura County districts map on Wikimedia Commons is in the public domain

    Several place names in the county have originated from Chumash, including Ojai, which means moon, and Simi Valley, which originates from the word Shimiyi and refers to the stringy, thread-like clouds that typify the region, also known as cirrus clouds. Other names include Point Mugu from the word Muwu meaning “beach”, Saticoy from the word Sa’aqtiko’y meaning “sheltered for the wind”, and Sespe Creek from the word S’eqp’e meaning “kneecap”.

    Spanish Period

    Mission San Buenaventura is a Spanish mission founded in 1782 by the Franciscan order.

    In October 1542, the expedition led by Juan Rodríguez Cabrillo anchored in an inlet near Point Mugu; its members were the first Europeans to arrive in the area that would become Ventura County.

    Active occupation of California by Spain began in 1769. Gaspar de Portolà led a military expedition by land from San Diego to Monterey, passing through Ventura County in August of that year. A priest with the expedition, Father Juan Crespí, kept a journal of the trip and noted that the area was ideal for a mission to be established and it was a "good site to which nothing is lacking". Also on this expedition was Father Junípero Serra, who later founded a mission on this site.

    On March 31, 1782, the Mission San Buenaventura was founded by Father Serra. It is named after Saint Bonaventure, one of the early intellectual founders of the Franciscan order. The town that grew up around the mission was originally named San Buenaventura (and retains the name officially), it has been known as Ventura since 1891.

    In the 1790s, the Spanish Governor of California began granting land concessions to Spanish Californians who were often retiring soldiers. These concessions were known as ranchos and consisted of thousands of acres of land that were used primarily as ranch land for livestock. In Ventura County, Rancho Simi was granted in 1795 and Rancho El Conejo in 1802. Fernando Tico was granted Ojai and part of Ventura by Gov. Alvarado.

    Mexican Period

    In 1822, California was notified of Mexico's independence from Spain and the Governor of California, the Junta, the military in Monterey and the priests and neophytes at Mission San Buenaventura swore allegiance to Mexico on April 11, 1822. California land that had been vested in the King of Spain was now owned by the nation of Mexico.

    By the 1830s, Mission San Buenaventura was in a decline with fewer neophytes joining the mission. The number of cattle owned by the mission dropped from first to fifteenth ranking in the California Missions. The missions were secularized by the Mexican government in 1834. The Mexican governors began granting land rights to Mexican Californians, often retiring soldiers. By 1846, there were 19 rancho grants in Ventura County. In 1836, Mission San Buenaventura was transferred from the Church to a secular administrator. The natives who had been working at the mission gradually left to work on the ranchos. By 1839, only 300 Indians were left at the Mission and it slipped into neglect.

    American Period

    The Mexican-American War that began in 1846, had its’ effect in Ventura County. In January of 1847, when Captain John C. Frémont led the California Battalion into San Buenaventura, and found that the Europeans had fled, leaving only the Indians at the Mission. Fremont and the Battalion continued south to sign the Treaty of Cahuenga with General Andrés Pico. The Treaty of Guadalupe Hidalgo formally transferred California to the United States in 1848.

    By 1849, California became a territory and was divided into 27 counties. The area that would become Ventura County was originally part of Santa Barbara County.

    In the 1860s, the area experienced a drought and many of the ranchos were divided and sold. The town of San Buenaventura was incorporated in 1866, becoming the first officially recognized town in what would become Ventura County.

    On January 1, 1873, Ventura County was officially split from Santa Barbara County. The Southern Pacific Railroad laid tracks through San Buenaventura in 1887. Other towns in the county were established in the late 19th century, including Oxnard, which was named after the Oxnard Brothers, who owned a sugar beet processing factory.

    Other towns were starting in the county. A plan for Hueneme, later called Port Hueneme, was recorded in 1874, and Santa Paula's plan was recorded in 1875. The community of Nordhoff, later renamed Ojai, was started in 1874. Bardsdale, Fillmore, Piru, and Montalvo were established in 1887. 1892 saw Simi, later Simi Valley, Somis, Saticoy, and Moorpark. Oxnard was a latecomer, not being established until 1898.

    The Southern Pacific Railroad laid tracks through San Buenaventura in 1887. For convenience in printing their timetables, Southern Pacific shortened San Buenaventura to Ventura. The Post Office soon followed suit. While the city remains officially known as San Buenaventura, it is more commonly referred to as Ventura. The rail line to Northern California originally went through Saugus, Fillmore, and Santa Paula, providing a boom to those communities along the line. In 1905, Tunnel #26 was completed between Chatsworth and Corriganville near Simi Valley, shortening the rail route. At a length of 7,369 feet (2,246 m), Tunnel #26 was the longest tunnel ever constructed in its day. This tunnel joined to the railroad spur coming the other direction from Montalvo through Camarillo, Moorpark, and Simi Valley, making the contemporary main line used today. One stop along the way, at a 90-degree turn, was at a sugar beet processing factory. The factory bore the name of its absentee owners, the Oxnard Brothers. A small community of farm and factory workers grew near the train stop. That community, now bearing the name of the factory shortened to the one-word train stop Oxnard, has become the largest city in Ventura County.

    Oil has been known in Ventura County since before the arrival of the Europeans. The first oil well in the county was drilled in 1914, but it was not until 1916 that the large South Mountain Oil Field was discovered. At its peak, the Ventura Avenue oilfield was producing 90,000 barrels of oil a day. Other oil fields came online in the 1920s and 1930s.

    Modern Period

    Ventura County can be separated into two major parts, East County and West County, which are divided by the Conejo Grade. East County consists of all cities east of the Conejo Grade. Geographically East County is the end of the Santa Monica Mountains, in which the Conejo Valley is located, and where there is a considerable increase in elevation. Communities which are in the East County are Thousand Oaks, Newbury Park, Lake Sherwood, Hidden Valley, Santa Rosa Valley, part of Westlake Village, Oak Park, Moorpark, and Simi Valley. Most of these communities are in the Conejo Valley.

    West County, which is everything west of the Conejo Grade, consists of communities such as Camarillo, Oxnard, Somis, Point Mugu, Port Hueneme, Ventura, Ojai, Santa Paula, and Fillmore. West County consists of some of the first developed cities in the county. The largest beach communities are in West County along the coastline between the Channel Islands Harbor and Ventura Harbor.

    Starting in the mid-20th century, there was a large growth in population in the East County, moving from the San Fernando Valley in Los Angeles and west into the Conejo and Simi Valleys. Part of the Conejo Valley is situated in Los Angeles County. This part consists of Calabasas, Hidden Hills, Agoura Hills, Agoura, and Westlake Village. The other half of the Conejo Valley, which belongs to Ventura County, consists of Lake Sherwood, Hidden Valley, Oak Park, Thousand Oaks, and Newbury Park, which was formerly an unincorporated area that is now the most westerly part of Thousand Oaks. Many working-class people migrated to this area during the 1960s and 1970s out of East and Central Los Angeles. As a result, there was a large growth in population into the Conejo Valley and into Ventura County through the U.S. Route 101 corridor. Making the U.S. 101 a full freeway in the 1960s, and the expansions that followed, helped make commuting to Los Angeles easier and opened the way for development westward. The communities that have seen the most substantial development are Calabasas, Hidden Hills, Agoura Hills, Westlake Village, Thousand Oaks, and Newbury Park. The neighboring East County area of Simi Valley saw its already considerable population of nearly 60,000 inhabitants in 1970 grow to over 100,000 over the following two decades.


    This page titled 9.4: Central Coast is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by Jeremy Patrich.

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