Misplaced Pages

#22977

52-762: The Santa Ynez Mountains are a portion of the Transverse Ranges , part of the Pacific Coast Ranges of the west coast of North America. It is the westernmost range in the Transverse Ranges. The range is a large fault block of Cenozoic age created by the movements of the Santa Ynez Fault . A very narrow range, the Santa Ynez Mountains rise quickly on its north side and drops off equally dramatically along

104-500: A marked change to red beds of river systems of Oligocene age in the western and central segments. Limestones and dolomites of the marine Miocene Monterey Formation are found in the Santa Ynez Mountains and in the Coast Ranges to the north. The distinctive feature of the Transverse Ranges besides their anomalous orientation is that they are bounded by east-west trending faults. Most are left slip, strike slip faults . In

156-532: A mix of sedimentary, volcanic, and metamorphic rocks, while regions east of the pass are dominated by plutonic granitic and metasedimentary rocks. The western and central segments of the Transverse Ranges are bounded to the north and east by the San Andreas Fault, which separates those segments from the Mojave Desert. The eastern segment bounds the southern Mojave Desert. Notable passes along

208-484: A modest 4,190 ft (1,277 m) above mean sea level ; this means that snow is less of a factor here than in the moderate to high mountain passes to the north like Donner Pass . Still sometimes, heavy snowfall can snarl traffic on Tejon and Cajon Pass, the higher two of the three freeway passes. I-5 and I-15 commonly experience heavy traffic over their mountainous route across these mountains. Cold Spring Canyon Arch Bridge The Cold Spring Canyon Arch Bridge in

260-569: A result, there is high topographic relief throughout the range, and other than in marginal areas (e.g. the San Fernando Valley ) and a few river valleys (such as Lockwood Valley and Big Bear Valley), there are no large, flat basins within the ranges. The mountains are notable for being steep and difficult to traverse. There are few passes that are sufficiently low or wide enough to accommodate significant volumes of traffic. This has resulted in situations where major cities are linked to

312-404: Is no rain between May and October. Most of the higher coastal slopes of the range average between 30 inches (760 mm) to almost 40 inches (1,000 mm) of precipitation per year (mostly falling between November and March), about twice the total of the coastal plain below. About one year in three snow falls on the higher peaks in the mountains, but it rarely stays for longer than a few days. In

364-631: The 2018 Southern California mudflows , may be cut off from timely road access to the rest of Southern California. Major peaks of the Transverse Ranges with at least 500 feet (150 m) of prominence, listed by height: This segment begins at Point Conception in Santa Barbara County, and include the Santa Ynez Mountains that run parallel to the coast behind Santa Barbara and the San Rafael Mountains on

416-610: The Mesozoic , mostly granites, can be found on Mount Pinos and generally in regions east of Tejon Pass . The youngest rocks are Cenozoic sedimentary and volcanic rocks that can be found throughout the ranges. The western segment is distinctive for the large thickness of Cretaceous and Cenozoic sedimentary rocks, estimated to be up to 10 kilometers. The thickest deposits of these are in the Santa Barbara Channel and Ventura basin. These are mostly marine in origin with

468-726: The Painted Cave community where Jane Fonda owned the ridgetop Laurel Springs Ranch into the late 1990s. Other famous residents have included Ronald Reagan , whose Rancho del Cielo is at the top of the range west of Santa Barbara, and Ben Adelson. The Cold Spring Tavern is a popular local gathering place beneath the Cold Spring Bridge . The climate of the mountain range is Mediterranean . Summers are warm and almost entirely rainless, save for occasional monsoonal showers in August and September, though in most years there

520-828: The Pinto , Eagle , and Orocopia Mountains are within the eastern segment. The Mojave Desert and California's low desert, including the Coachella Valley , are at the eastern end of the ranges. Ranges north of the western segment that are nearly transverse but are part of the California Coast Ranges include the San Rafael Mountains and the Sierra Madre Mountains . Likewise, the Tehachapi Mountains north of

572-517: The Santa Ynez Fault , a feature which is considered to be active. The left bend in the San Andreas Fault is proposed to have constrained northward moving lithosphere to cause uplift of the range. Being a young uplift, the slopes are steep and the topography is extremely rugged; the gradient is highest on the northern side above 1,500 feet (460 m), adjacent to the trace of the fault. Dramatic sandstone formations, including outcrops of

SECTION 10

#1732765102023

624-477: The Santa Ynez Mountains links Santa Barbara, California with Santa Ynez, California . The bridge is signed as part of State Route 154 . It is currently the highest arch bridge in the U.S. state of California and among the highest bridges in the United States . At its highest point, the bridge deck is 400 ft (122 m) above the canyon floor. The bridge is also the largest steel arch bridge in

676-642: The WWF -designated California montane chaparral and woodlands ecoregion , but the eastern points of the range touch two desert regions, the Mojave Desert and the Colorado Desert section of the Sonoran Desert . The Carrizo Plain adjoins the northern edge of the Transverse Range. Chaparral is a common feature of the Transverse Ranges. Common plant associates in chaparral , especially in

728-475: The most important oil-producing areas in the United States. The plant place of the Transverse ranges include coastal sage scrub , oak woodland and savanna , and pinyon-juniper woodland at lower elevations, and yellow pine forest , Lodgepole Pine , and subalpine forest at higher elevations. The Angeles and Los Padres National Forests cover portions of the Transverse ranges. The ranges are part of

780-571: The Mojave Desert, although nearly transverse, are the southern end of the Sierra Nevada . Mountain ranges with peaks exceeding 4,500 feet (1,400 m), listed west to east, include: Examples of smaller mountain and hill ranges include: The climate in most of the range is Csb ( Warm-summer Mediterranean ) under the Köppen climate classification ; the upper reaches of San Gorgonio Mountain have an alpine tundra climate ( ET ), while

832-675: The San Andreas fault include Tejon Pass , Cajon Pass , and San Gorgonio Pass . Components of Transverse Ranges to the north and east of the fault include the San Bernardino Mountains , Little San Bernardino Mountains , Pinto and Eagle Mountains . The western and southern boundaries are acknowledged to be the Pacific Ocean and the northern Channel Islands . Onshore the Los Angeles Basin lies at

884-546: The San Andreas fault) have the highest elevations. Most of the ranges lie in the California chaparral and woodlands ecoregion. Lower elevations are dominated by chaparral and scrubland, while higher elevations support large conifer forests. Most of the ranges in the system are fault blocks , and were uplifted by tectonic movements late in the Cenozoic Era . West of Tejon Pass , the primary rock types are varied, with

936-681: The Santa Barbara Channel and Ventura Basin. Much oil has pooled in the Monterey Formation, which is produced onshore and offshore. In the eastern Santa Barbara Channel oil is held in younger sedimentary rocks. The Los Angeles Basin south of the western segment, formed during rotation of that segment away from the Peninsular Ranges. It is also a site of prolific oil production. The California Geologic Survey states: Great thicknesses of Cenozoic petroleum-rich sedimentary rocks have been folded and faulted, making California one of

988-563: The Transverse Ranges and the Peninsular Ranges to the south. There are a number of important freeways that cross the Transverse Ranges, such as (from west to east) US-101, I-5 at Tejon Pass , SR 14 at Soledad Pass , and I-15 at Cajon Pass . These highways link Southern California with places to the north and northeast like San Francisco and Las Vegas , respectively. With the exception of several high passes on less-traveled SR 33 , SR 2 , SR 330 . SR 18 and SR 38 , none of these passes are at high elevations, with Cajon Pass being at

1040-977: The Transverse Ranges; San Miguel , Santa Rosa , Santa Cruz and Anacapa Islands are a westward extension of the Santa Monica Mountains. The Ranges include the steep San Gabriel Mountains northeast of Los Angeles , the Sierra Pelona Mountains just south of the San Andreas fault, the Tehachapi Mountains southeast of Bakersfield, the Verdugo Mountains , the Liebre-Sawmill Mountains, the San Rafael Hills , Puente Hills , San Jose Hills , and Chino Hills . The San Bernardino Mountains , Little San Bernardino Mountains , and

1092-612: The bounding faults are left slip Santa Ynez and Pine Mountain Faults. The San Gabriel Fault and San Andreas bound the central segment. The eastern segment is bounded by the Pinto Mountain Fault in the north and the Salton Creek Fault in the south. The large thickness of marine sediments in the western segment have made it a habitat for oil. Several dozen fields are found onshore and offshore, particularly in

SECTION 20

#1732765102023

1144-612: The central and eastern segments, including the San Gabriel and San Bernardino Mountains. The oldest basement (deepest) rocks are of Proterozoic age, and are found in the San Gabriel Mountains and the San Bernardino Mountains. The Jurassic - Cretaceous Franciscan Assemblage is found in the western section of the ranges and is the presumed basement in this segment. Exposed plutonic rocks from

1196-557: The city of Santa Barbara, driven by sundowner winds, destroying over 500 homes. A fire in the 1940s destroyed most of the mansion that is now called Knapp's Castle . More recent fires, such as the Tea and Jesusita fires, have also been destructive to properties. Transverse Ranges The ranges extend from west of Point Conception eastward approximately 500 kilometers into the Mojave and Colorado Desert . The geology and topography of

1248-518: The fault moved east to open the Gulf of California . The crust within the Pacific Plate south of the ranges can not easily make the left turn westward as the entire plate moves northwestward, forcing pieces of the crust to compress and lift. Prior to this shift of the fault to create the left bend, northwest–southeast trending rock belts in all of the Transverse Ranges began to rotate clockwise in

1300-418: The faults outside that province. Between the western segment and the Peninsular Ranges to the south is the complex Malibu Coast—Santa Monica— Hollywood fault , which exists as the border between these two mostly geologically unitary provinces. These faults are part of the same thrust fault system south of the northern Channel Islands of San Miguel, Santa Rosa, and Anacapa Islands. North of the western segment

1352-618: The few in the United States. This is attributed in part to clockwise rotations of crustal blocks 90° or more since the early Miocene or about 17 million years ago. The range is mostly within Los Padres National Forest . The southern slopes of the range drop off into a series of alluvial plains which make up the Gaviota Coast along the Santa Barbara Channel. They tend to be made up of unconsolidated riverine deposits overlying shale bedrock. The northern boundary of

1404-591: The interaction of the Pacific Plate and the North American Plate along the dextral (right slip) San Andreas Fault system. Their orientation along an east–west axis as opposed to the general northwest–southeast trend of most California ranges results from a pronounced left step in the San Andreas Fault that occurred in the Pliocene ( c.  4 million years ago) when southern reaches of

1456-433: The late spring and early summer the mountains and areas below to the south are subject to occasional intense sundowner winds , a type of foehn wind in which the air is heated adiabatically and dried as it moves downslope. In dry years these winds pose an extreme fire hazard. Occasionally extremely destructive fires originate in the Santa Ynez Mountains. In June 1990, a fire which began near Painted Cave burned south into

1508-458: The latter of which wanders in and out of the range within territories in excess of 15 square miles. Early inhabitants included the Chumash people who left behind many examples of rock art including those at Painted Cave SHP . Large portions of the mountain range are now in the Los Padres National Forest , although there are private inholdings , including some substantial communities, such as

1560-451: The lower northern slopes of the range have a desert ( BW ) or steppe ( BS ) climate; most of the nearby lowlands to the south and west have a Hot-summer Mediterranean climate ( Csa ). Snow falls above 6,000 feet (1,800 m) most winters, and above 3,000 feet (910 m) every few years. It is rare for elevations above 8,000 feet (2,400 m) to go multiple winters without snow, even during severe droughts. Due to relatively low humidity,

1612-849: The mountain range diverges into two low ridges, separated by Jalama Creek, which then vanish into the Pacific Ocean. The mountains parallel the Channel Islands to the south, another east–west trending range, a geologic extension of the Santa Monica Mountains ; the two ranges are about thirty miles apart. Principal summits in the Santa Ynez range include Divide Peak, 4,707 ft (1,435 m), La Cumbre Peak , 3,985 ft (1,215 m) (above Santa Barbara), and Santa Ynez Peak, 4,298 ft (1,310 m). There are several important passes, including Gaviota Pass in

Santa Ynez Mountains - Misplaced Pages Continue

1664-696: The mountain ranges, including the Oxnard Plain of coastal Ventura County , the Santa Clarita Valley north of Los Angeles, the San Fernando Valley , which is mostly included in the City of Los Angeles. The Los Angeles Basin, which includes the portion of Los Angeles County south of the Santa Monica Mountains and most of Orange County , and the Inland Empire basin, which includes the cities of San Bernardino and Riverside , lie between

1716-656: The mountains are young and mostly of sedimentary origin. The most common rock types in the range are sandstones and shales, with some limestone in the western portion of the range. Volcanic rocks can be found at the very western extremity of the range, near Point Arguello (Tranquillion Mountain Volcanics), while some schists of the Franciscan Assemblage are exposed in a number of locations. The Santa Ynez Mountains were uplifted in Pliocene and Pleistocene time, beginning about five million years ago, along

1768-499: The mountains extend from an eastern terminus at the canyon of the Ventura River and Matilija Creek, north of Ojai , west across the Santa Barbara County line, to immediately north of the city of Santa Barbara , and then west, paralleling the coast, to the city of Lompoc and Vandenberg Space Force Base . The Santa Ynez River flows just north of the mountains, paralleling them for most of their length. Before reaching Lompoc

1820-874: The other side of the Santa Ynez Valley . The western Transverse Ranges also include the Topatopa Mountains and the Santa Susana Mountains of Ventura County and Los Angeles County, the Simi Hills , the Santa Monica Mountains that run along the Pacific coast behind Malibu , and whose eastern portion are known as the Hollywood Hills , and the Chalk Hills . The northern Channel Islands of California are also part of

1872-497: The outboard Pacific plate. Because the Monterey plate was then beneath southern California, the capture resulted in pulling of the overlying crust out and northward from the rest of California. Rocks of the Transverse Ranges exhibit extreme differences in geologic age and composition, varying from sedimentary rocks in the western Santa Ynez and volcanic rocks in the Santa Monica Mountains to primarily granitic and metamorphic rock in

1924-653: The range is Mediterranean with most of the precipitation falling between November and March. Most of the range lies in the California chaparral and woodlands ecoregion. At the crest and on the north slope, the rainier regions support extensive oak woodlands, mixed with other broadleafed species such as madrone, sycamore and bay laurel, along with some conifers, primarily Coulter pines . The mountains are principally in Santa Barbara County , with an eastward extension into Ventura County , and are unusual in being an entirely east–west trending mountain range—one of

1976-541: The range is marked by the Santa Ynez Fault, the massive thrust fault that uplifted the mountains since approximately 5 million years ago starting in the Pliocene . Notable features along the fault which mark the boundary of the range include Jalama Creek and the Santa Ynez River to the west and Matilija Creek in the far east. To the north of the range are the San Rafael Mountains . Laterally,

2028-402: The range's south face along the Gaviota Coast . The Santa Ynez Mountains begin as a series of volcanic hills near Point Arguello , and gradually transitions eastward into a single, well-defined ridge extending from Gaviota Peak to Matilija Creek . The range is approximately contiguous with the Topatopa Mountains beyond to the east, which terminates abruptly at Sespe Creek . The climate of

2080-612: The ranges express three distinct segments that have contrasting elevations, rock types, and vegetation. The western segment extends to the San Gabriel Mountains and San Gabriel fault . The central segment includes mountains that range eastward to the San Andreas fault . The eastern segment extends from the Cajon Pass at the San Andreas fault eastward to the Colorado Desert. The central and eastern segments (near

2132-420: The regional snow line lies at about 14,000–16,000 feet (4,300–4,900 m), above the highest elevation of the range; as such, snow does not persist year-round except in the form of snow patches . The tree line lies at about 11,000 feet (3,400 m); San Gorgonio Mountain is the only peak with an alpine environment. The Transverse Ranges result from a complex of tectonic forces and faulting stemming from

Santa Ynez Mountains - Misplaced Pages Continue

2184-431: The resistant Coldwater and Matilija formations, are visible at many locations in the range. The predominant ground cover is chaparral , with coastal sage scrub , oak woodland and grasslands at lower elevations. Isolated stands of conifers (mostly Coulter pines ) and other evergreen trees such as bay laurel , tanbark oak and madrone grow on the higher parts of the northern slopes, which are cooler and shadier than

2236-531: The rest of the state by relatively few roads; for example, the vast majority of traffic between the Central Valley and the Los Angeles area is routed through Tejon Pass. This results in significant traffic issues throughout Southern California when a pass has to be shut down due to heavy snow or construction. Occasionally, major cities, such as Santa Barbara during the 2005 La Conchita landslide and

2288-547: The right shear of Pacific Plate – North American Plate motion. This tectonic rotation began in Early Miocene Time and continues today. The total rotation is about 90° in the Western Transverse Ranges and less (about 40°) in the eastern ranges. Catalina Island shows the most rotation: almost 120°. A mechanism proposed for the rotation event is capture of the subducting Monterey plate by

2340-504: The southern boundary of the western and central segments of the ranges. Major passes not along the San Andreas Fault include Gaviota Pass , San Marcos Pass , the Conejo Grade , Newhall Pass , and Cahuenga Pass . The Transverse Ranges manifest themselves as a series of roughly parallel ridges with an average height of 3,000–8,000 feet (910–2,440 m). The ranges are dissected by young, steep streams of relatively low flow rate; as

2392-603: The southern slopes exposed to the sun. At lower elevations on the southern side of the range, a virtually frost-free zone, avocados are grown in considerable quantity. The Santa Ynez Mountains are home to many species typical of the California chaparral and woodlands ecoregion, such as the Western fence lizard , Nuttall's woodpecker , Steller's jay , striped skunk , raccoon , mule deer , bobcat , and coyote . Large predator species include mountain lion and black bear ,

2444-565: The state. It was determined to be eligible for the National Register of Historic Places with exceptional significance. The current bridge was completed and opened to traffic in February 1964. It was constructed by U.S Steel Corp's American Bridge division and Massman Construction Co. The structure won awards for engineering, design, and beauty. It was in the top 5 longest span arch bridges of this "supported deck" type in

2496-506: The transition between coastal chaparral and coastal sage scrub, include California sagebrush and Toyon , the latter shrub having its southern distribution limit defined by the Transverse Ranges. Pinyon-juniper woodland is common on the north slopes of the San Gabriel and San Bernardino Mountains. This ecosystem is easily visible in the well-travelled Soledad Pass region, between Pearblossom and Santa Clarita . A number of densely populated coastal plains and interior valleys lie between

2548-450: The western and central segments many of the faults are thrust faults . Faults in the Coast Ranges and Peninsular Ranges trend northwest-southeast and butt into the east-west trending faults of the Transverse Ranges. Because all of these faults are considered active and seismic but they do to cut each other, the only geometry that satisfies that observation is if the east-west faults and Transverse Ranges are rotating clockwise with respect to

2600-524: The western portion of the range, through which runs U.S. Highway 101 via the Gaviota Tunnel ; and San Marcos Pass near Santa Barbara, through which runs California State Route 154 capped by the magnificent Cold Spring Canyon Arch Bridge near the summit. The highest point, an unnamed and unmarked crest colloquially called Peak 4864 , is located right above the eastern terminus of the range, near Lake Casitas and Matilija Canyon. Geologically

2652-496: The world until the 1990s. Cold Spring Tavern , originally a stagecoach stop, is approximately 600m south of the bridge's west base in the canyon below, on a stub of Old San Marcos Pass Road (now named Stagecoach Rd.) connecting with SR 154 at Camino Cielo and Paradise Roads. The bridge was designated as a Historic Civil Engineering Landmark by the American Society of Civil Engineers in 1976. Seismic retrofitting

SECTION 50

#1732765102023

2704-422: Was completed in 1998 by American Bridge , one of the companies involved in the original construction. As of March 2012 , the bridge had been the site of 55 suicides since its completion, which is about one per year on average; however, some years have several more suicides, such as the eight deaths recorded in 2009. In an effort to prevent future incidents, California Department of Transportation installed

#22977