Serra Fault

Serra Fault

The Serra Fault is the northernmost fault in a zone of northwest-striking range front thrust faults adjacent to and northeast of the San Francisco Peninsula segment of the San Andreas Fault (Kennedy, 2005). The Serra Fault is positioned approximately 1.5 to three kilometers northeast of the San Andreas Fault ; moreover the Serra Fault extends for more than 20 kilometres from the town of Hillsborough to a point near Daly City. According to Kennedy: "Three angular unconformities within the Merced and overlying Colma Formations have formed on the steeply dipping fold forelimb". Mid to later Holocene fluvial channel deposits inset into the Merced Formation along the forelimb of the fold seem to be deformed, illustrating that the folding is active.

The Serra Fault is a low angle imbricate fault that has thrust older Franciscan Assemblage rocks and soils of the Merced Formation over the younger Colma Formation. The Serra Fault was originally zoned as potentially active by the State of California (California, 1974) under the mandated special studies for surface fault rupture. 1980s studies concluded that evidence for active Holocene age faulting (displacement within past 11,000 years) along the Serra Fault is lacking. (Earth Metrics, 1989) The Serra Fault is, therefore, not zoned for Special Studies by the State of California and is classified as Quaternary in age: that is, fault displacement within the past two million years.

Regional geology

Age constraints for coastal exposures of the Pleistocene Colma and uppermost Merced Formations have prior to 2005 been primarily correlative, generating uncertainty about the depositional history of these units as well as the timing of fault activity responsible for lifting them to elevations up to seventy meters along the northwestern coast of the San Francisco Peninsula. Yi notes that: "Recent studies have suggested that Merced and Colma deposits, as well as younger Holocene inset channel deposits, show fault-propagation fold growth and tilting" related to activity on the Serra Fault itself. (Yi, 2005)

ee also

*Crystal Springs Reservoir
*Hillside Fault

Reference notes

* Kennedy, Drew G., "LATE PLEISTOCENE TO HOLOCENE FOLD GROWTH ABOVE THE SERRA FAULT, NORTHERN SAN FRANCISCO PENINSULA, CALIFORNIA", Sanders & Associates Geostructural Engineering, Geological Society of America (2005)
*California Division of Mines and Geology, "Special Studies Zone:Serra Fault", (1974) Sacramento, California
*Earth Metrics, (1989) Marc. Papineau, Ballard. George, Jill Buxton et al., "Environmental Impact Report for the Metro Center, Colma, California", Rpt Number 10062, city of Colma Planning Department and published by the California State Clearinghouse, December, 1989
*"Chimi Yi, Karen Grove, John Caskey, Drew Kennedy, and Glenn Berger, "Depositional and Deformational History of the Colma and Uppermost Merced Formations, Southwest San Francisco", (2005), Geological Society of America

External links

* [http://www.ncgeolsoc.org/FieldTripInfo/Merced%20Formation%20Field%20Trip.htm Richard Cardwell, "Merced Formation Field Trip] ]


Wikimedia Foundation. 2010.

Игры ⚽ Поможем сделать НИР

Look at other dictionaries:

  • Newport-Inglewood Fault — The Newport Inglewood Fault is a right lateral fault in Southern California. The fault extends for 75 kilometers (47 mi) from Culver City southeast to Newport Beach at which point it runs out into the Pacific Ocean. The fault can be seen on… …   Wikipedia

  • Clayton-Marsh Creek-Greenville Fault — This fault is shown in white and is the rightmost fault The Clayton Marsh Creek Greenville Fault is a fault located in the eastern San Francisco Bay Area of California, in Alameda County and Contra Costa County. It is part of the somewhat… …   Wikipedia

  • Death Valley Fault Zone — The Death Valley Fault Zone (DVFZ) is a right lateral moving (dextral) geologic fault in eastern California. It runs from a connection with the Furnace Creek Fault Zone in the Amargosa Valley southward to a junction with the Garlock Fault. It is… …   Wikipedia

  • Chino Fault — The Chino Fault is a fault that extends along the eastern Chino Hills range region, from Corona in Riverside County to the Los Serranos, Chino Hills area of San Bernardino County in Southern California. Geology The Chino Fault and Whittier Fault… …   Wikipedia

  • Mount Diablo Thrust Fault — The Mount Diablo Thrust Fault, also known as the Mount Diablo Blind Thrust, is a thrust fault in the vicinity of Mount Diablo in Contra Costa County, California. The fault lies between the Calaveras Fault, the Greenville Fault, and the Concord… …   Wikipedia

  • Junipero Serra Landfill — The Junipero Serra Landfill was a solid waste disposal site in Colma, California, USA. The site was closed in 1983 and ultimately developed by commercial land uses, collectively known as the Metro Center. The original commercial use built on the… …   Wikipedia

  • Mendocino Fracture Zone — The Mendocino Fracture Zone between the Gorda Plate and Pacific Plate The Mendocino Fracture Zone is a fracture zone and transform boundary off the coast of Cape Mendocino in far northern California. It runs westward from a triple junction with… …   Wikipedia

  • Mendocino Triple Junction — The Mendocino Triple Junction is a geologic triple junction where the San Andreas Fault meets the Mendocino Fault and the Cascadia subduction zone, separating three tectonic plates: the Pacific Plate, the North American Plate and the Gorda Plate …   Wikipedia

  • Maria fold and thrust belt — Ranges, Plains Thrusted Forms Country United States States …   Wikipedia

  • Daly City, California — City of Daly City   City   Part of Daly City with San Bruno Mountain and the San Francisco neighborhood of Crocker Amazon in the background …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”