South Cuyama Oil Field
The South Cuyama Oil Field is an extensive oil and gas exploitation area in the Cuyama Valley and the neighboring foothills of the Sierra Madre Mountains in northeast Santa Barbara County , California . It was discovered in 1949 and has since produced a total of 225 million barrels of oil. It ranks 27th in California. According to estimates by the California Department of Oil, Gas, and Geothermal Resources (DOGGR), only two percent of the original deposit has not yet been produced, about 4.6 million barrels. Of the forty richest oil fields in California, South Cuyama is the most recently discovered. In 2006, however, only 84 wells were still in operation.
location
The oil field is located south of the city of New Cuyama in the part of the Cuyama Valley that clings to the northern foothills of the Sierra Madre Mountains. Parts of the field are in hilly terrain and part is within the Los Padres National Forests . The field is accessible via California State Route 166 ; Aliso Canyon Road connects it to the trunk road from the northwest and Perkins Road connects to Route 166 in the town of New Cuyama. Foothill Road traverses the oil field in a west-east direction and leads to Santa Barbara Canyon Road and California State Route 33 . The site is between 670 and 910 meters above sea level. The productively used part of the oil field measures about eight by four kilometers, with the longer axis running from northwest to southeast; the area is given by the DOGGR as 2650 acres , about 1000 hectares .
The area is prone to bush fires. In 1994, one such fire caused US $ 76,000 in damage and in July 2006 an accident caused the Perkins Fire to break out . A piece of metal had shorted power lines and started the fire, which burned 15,000 acres of land on the north side of the Sierra Madre Mountains.
The original vegetation around the oil wells ranges from grasslands to chaparral to oak forests. The area drains through Bitter Creek, Branch Canyon Wash, and several unnamed watercourses north to the Cuyama River .
geology
The oil in the South Cuyama Basin comes from two primary oil-bearing strata. In the Miocene , the Dibblee Sand and Colgrove Sand deposits emerged, porous units in the Vaqueros Formation below the largely impermeable Monterey Formation . The sedimentary Cuyama Basin is criss-crossed by several smaller faults and the oil deposits are located in a series of stratographic chambers that are capped at the top by the impermeable Monterey Formation. The average depth of the deposits is about 1250 m below the surface and the thickness of the oil-bearing layer barely exceeds 60 m; in the separated south-eastern part of the oil field called Colgrove Sand, the oil-bearing layer is 1,780 m below the surface and is less than 15 m thick. The source rock for the South Cuyama Oil is believed to be the Soda Lake Shale of the Vaqueros Formation.
Above the folded and broken rock layers from the Miocene, to which the Monterey, Branch Canyon and Santa Margarita formations belong, lies the 600–750 m thick Morales Formation, which was separated by a discordance and formed in the Pliocene . None of these upper strata are oil-bearing, but natural gas was produced from the Santa Margarita Formation.
The oil from the South Cuyama field has a medium to high API grade of 28-36 , so that it is an easy-flowing oil. A small deposit in Dibblee Sand in the Southeast Area of the field, abandoned today, has an even higher gravity. The spring here was tapped in 1975 and abandoned in 1978 after 48,000 barrels had been extracted.
history
Richfield Oil Co., later part of the Atlantic Richfield Company (ARCO), carried out the first test wells here in May 1949 on the advice of Thomas Dibblee . Richfield named the oil layer Dibblee Sand in his honor. This first well initially produced 525 barrels a day, which was considerable for an area that had previously been written off as not promising. The discovery of oil changed the then almost uninhabited Cuyama Valley, in which only a few ranches were raised. ARCO built the town of New Cuyama in the years following the oil discovery to house the oil workers and provide related services.
ARCO was the first of several companies that operated here. Stream Energy and then Hallador Petroleum, which operated the oil field until 2005, were active here. At that time, the company sold the production facilities to E&B Natural Resources Management Corporation, which currently operates the production. E&B operates a natural gas processing plant in the east of the oil field, where all the natural gas produced is handled.
Production at South Cuyame peaked in 1951 when 14 million barrels of oil were pumped from the Dibblee and Colgrove deposits just a few years after the discovery. Since then, production has steadily declined. It reached 820,000 barrels in 1977, around 500,000 barrels in 1987, 390,000 barrels in 1997 and only 270,000 barrels in 2007. At the end of 2006, 84 oil wells were still operating in the area.
Since the oil in South Cuyama is not heavy, no steam injection was necessary to reduce viscosity and improve fluidity, although water and natural gas were pumped into both the Colgrove and Dibblee sand. Between 1956 and 1973, water was pumped into the Colgrove sand with some success and the Dibblee began using water from 1955 and natural gas from 1964. Pumping in water is still used by E&B Resources as a technology to support the oil pumps .
swell
- California Oil and Gas Fields, Volumes I, II and III . Vol. I (1998), Vol. II (1992), Vol. III (1982). California Department of Conservation, Division of Oil, Gas, and Geothermal Resources (DOGGR). 1472 pages. Pages 120-124. PDF file available on CD from www.consrv.ca.gov.
- California Department of Conservation, Oil and Gas Statistics, Annual Report, December 31, 2006.
Individual evidence
- ↑ a b Oil and Gas Statistics ( English , PDF) In: Annual Report . California Department of Conservation. December 31, 2006. Retrieved September 4, 2008.
- ↑ DOGGR, p. 121
- ↑ Hallador Petroleum Co. ( English ) In: 1995 3rd Quarterly Report - Small Business Form 10-QSB . Hallador Petroleum. 1995. Retrieved September 4, 2008.
- ↑ Southern California wildfire summary for 2006 ( English ) Archived from the original on May 17, 2008. Information: The archive link was automatically inserted and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Retrieved September 4, 2008.
- ↑ Ecological subregions of California ( English ) Retrieved on 4 September, 2008.
- ↑ DOGGR, pages 120-121
- ↑ provenance of oil in southern Cuyama basin, California ( English ) Retrieved on 4 September 2008. (Abstract of a paper, which at a conference of the American Association of Petroleum Geologists has been submitted.)
- ↑ DOGGR, page 120
- ↑ Thomas Dibblee Jr .: Driven by scientific curiosity ( English ) In: Geotimes . Santa Barbara Museum of Natural History website. May 1992. Archived from the original on August 27, 2008. Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Retrieved September 4, 2008.
- ^ E&B Resources ( English ) County of Santa Barbara Energy Division. Archived from the original on August 30, 2008. Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Retrieved September 4, 2008.
- ↑ Hoovers profiles of Hallador Petroleum ( English ) Retrieved on 4 September, 2008.
- ↑ Oil and Gas Statistics ( English , PDF) In: Annual Report . California Department of Conservation. December 31, 2006. Retrieved September 4, 2008.
- ^ DOGGR, page 123
