The Temblor Range is a mountain range within the

California Coast Ranges The Coast Ranges of California span from Del Norte or Humboldt County, California, south to Santa Barbara County. The other three coastal California mountain ranges are the Transverse Ranges, Peninsular Ranges and the Klamath Mountains. P ...

, at the southwestern extremity of the

San Joaquin Valley The San Joaquin Valley ( ; es, Valle de San Joaquín) is the area of the Central Valley of the U.S. state of California that lies south of the Sacramento–San Joaquin River Delta and is drained by the San Joaquin River. It comprises seven c ...

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

. It runs in a northwest-southeasterly direction along the borders of

Kern County Kern County is a county located in the U.S. state of California. As of the 2020 census, the population was 909,235. Its county seat is Bakersfield. Kern County comprises the Bakersfield, California, Metropolitan statistical area. The county sp ...

and

San Luis Obispo County San Luis Obispo County (), officially the County of San Luis Obispo, is a county on the Central Coast of California. As of the 2020 census, the population was 282,424. The county seat is San Luis Obispo. Junípero Serra founded the Miss ...

. The name of the range is from Spanish ''temblor'' meaning "tremor", referring to earthquakes. The

San Andreas Fault Zone The San Andreas Fault is a continental transform fault that extends roughly through California. It forms the tectonic boundary between the Pacific Plate and the North American Plate, and its motion is right-lateral strike-slip (horizontal). ...

runs parallel to the range at the base of its western slope, on the eastern side of the Carrizo Plain, while the Antelope Plain, location of the enormous Midway Sunset, South Belridge, and Cymric

oil field A petroleum reservoir or oil and gas reservoir is a subsurface accumulation of hydrocarbons contained in porous or fractured rock formations. Such reservoirs form when kerogen (ancient plant matter) is created in surrounding rock by the presence ...

s, lies to the northeast. Peaks within the Temblor Range average about above sea level. The highest point is McKittrick Summit at , located in the center of the range about west of

Bakersfield Bakersfield is a city in Kern County, California, United States. It is the county seat and largest city of Kern County. The city covers about near the southern end of the San Joaquin Valley and the Central Valley region. Bakersfield's populat ...

. The summit on State Route 58, which crosses the range, is at above sea level. The lowest crossing of the range is at

Polonio Pass Polonio Pass is a low mountain pass that separates the Temblor Range to the south, and the Diablo Range to the north, linking Kern County, California, in the Central Valley, to Shandon and Paso Robles in San Luis Obispo County, both in the Ame ...

at by State Route 46 at its northern end and is separated by the

Diablo Range The Diablo Range is a mountain range in the California Coast Ranges subdivision of the Pacific Coast Ranges in northern California, United States. It stretches from the eastern San Francisco Bay area at its northern end to the Salinas Valley are ...

to the north near Cholame.

Origin and composition

The Temblor Range and surrounding region contains extensive outcrops of the

Monterey Formation The Monterey Formation is an extensive Miocene oil-rich geological sedimentary formation in California, with outcrops of the formation in parts of the California Coast Ranges, Peninsular Ranges, and on some of California's off-shore islan ...

(

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

age, about 20 to 9 million years). Rocks from the Monterey formation consist mostly of

silicate In chemistry, a silicate is any member of a family of polyatomic anions consisting of silicon and oxygen, usually with the general formula , where . The family includes orthosilicate (), metasilicate (), and pyrosilicate (, ). The name is al ...

shale Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4) and tiny fragments (silt-sized particles) of other minerals, especial ...

s and

porcellanite Porcellanite or ''porcelanite'', is a hard, dense rock somewhat similar in appearance to unglazed porcelain. It is often an impure variety of chert containing clay and calcareous matter. Porcellanite has been found, for example, in Northern Ir ...

(silica derived from

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

plankton Plankton are the diverse collection of organisms found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankt ...

in an intermediate to deep-water marine setting). Fossils and sediments from the Monterey Formation show that the Carrizo Plain region was a marine basin with shallow to intermediate depths (marine waters covered the southern

region). Marine sediments younger than about 9 million years are not preserved in the Carrizo Plain National Monument area, but they occur throughout the

Kettleman Hills The Kettleman Hills is a low mountain range of the interior California Coast Ranges, in western Kings County, California. It is a northwest–southeast trending line of hills about 30 miles long which parallels the San Andreas Fault to the west. ...

region (about north of the park). The

Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58Etchegoin Formation The Etchegoin Formation is a Pliocene epoch geologic formation in the lower half of the San Joaquin Valley in central California.Coast Ranges The Pacific Coast Ranges (officially gazetted as the Pacific Mountain System in the United States) are the series of mountain ranges that stretch along the West Coast of North America from Alaska south to Northern and Central Mexico. Although th ...

and the Temblor Range are young, having been uplifted mostly during the

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...

Epoch (or

Quaternary Period The Quaternary ( ) is the current and most recent of the three period (geology), periods of the Cenozoic era (geology), Era in the geologic time scale of the International Commission on Stratigraphy (ICS). It follows the Neogene Period and spa ...

) in the past several million years. Much of that ongoing uplift is due to

tectonics Tectonics (; ) are the processes that control the structure and properties of the Earth's crust and its evolution through time. These include the processes of mountain building, the growth and behavior of the strong, old cores of continents k ...

associated with the San Andreas Fault and other fault systems in the region. During the Pleistocene, sometime more recently than 1.8 million years ago, an enormous block of the Temblor Range – a swath of Monterey shale more than long, a mile across, and over thick, about three cubic miles of rock in all – slid down the northeastern side of the range, covering a distance of approximately three miles and descending . This mass movement completely covered the

McKittrick Oil Field The McKittrick Oil Field is a large oil and gas field in western Kern County, California. The town of McKittrick overlies the northeastern portion of the oil field. Recognized as an oil field in the 19th century, but known by Native Americans fo ...

, giving it a highly unusual geology for an oil field, as the petroleum deposits in most oil fields are in structural or stratigraphic traps; this field is capped by an enormous mass of rock that moved off of the adjacent mountain range.J.A. Taff: "Geology of the McKittrick Oil Field and Vicinity, Kern County, California." American Association of Petroleum Geologists Bulletin, 193
(abstract available here)
/ref> The Temblor Range is delineated from the

San Emigdio Mountains The San Emigdio Mountains are a part of the Transverse Ranges in Southern California, extending from Interstate 5 at Lebec and Gorman on the east to Highway 33–166 on the west. They link the Tehachapis and Temblor Range and form the southern ...

and the

Santa Ynez Mountains 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 create ...

by State Route 166 in

Maricopa Maricopa can refer to: Places * Maricopa, Arizona, United States, a city ** Maricopa Freeway, a piece of I-10 in Metropolitan Phoenix ** Maricopa station, an Amtrak station in Maricopa, Arizona * Maricopa County, Arizona, United States * Marico ...

. This is the Temblor Range's southern end. The Temblor Range is delineated from the

and State Route 46, connecting the Central Valley and the Central Coast. This is the range's northern end near Cholame

Temblor Recreation Area

Th
Temblor Recreation Area
is less than 3 miles Southwest of

Taft, California Taft (formerly Moron, Moro, and Siding Number Two) is a city in the foothills at the extreme southwestern edge of the San Joaquin Valley, in Kern County, California. Taft is located west-southwest of Bakersfield, at an elevation of . The popula ...

. Although there are numerous unofficial routes into the area, legal public access is currently limited.

References

External links

*
USGS.gov: Carrizo Plain National Monument
— ''3D photographic tour featuring park's geology''. {{Authority control California Coast Ranges Mountain ranges of Kern County, California Mountain ranges of San Luis Obispo County, California Geography of the San Joaquin Valley Geology of Kern County, California Mountain ranges of Southern California