Rincon Oil Field
Encyclopedia
The Rincon Oil Field is a large oil field
on the coast of southern California, about ten miles northwest of the city of Ventura
, and about 20 miles east-southeast of the city of Santa Barbara
. It is the westernmost onshore field in a series of three fields which follow the Ventura Anticline, an east-west trending feature paralleling the Transverse Ranges
. Discovered in 1927, the oil field is ranked 36th in California by size of recoverable oil reserves, and while mostly depleted – now having, by California Department of Conservation estimates, only about 2.5% of its original oil – it remains productive, with 77 wells active at the beginning of 2008. Oil produced in the field flows through the M-143 pipeline, which parallels U.S. Highway 101 southeast to the Ventura Pump Station, at which point it joins a Tosco pipeline which carries it to Los Angeles area refineries. As of 2009, the primary operators of the field were Occidental Petroleum
for the onshore portion, and Greka Energy
for the offshore portion. The offshore part of the field is operated mainly from Rincon Island
.
, which attain heights of over 2100 feet at Rincon Mountain and Red Mountain. Highway 101 occupies the narrow terrace at the base of the hills where they meet the Pacific Ocean. Drainage is by ephemeral streams directly into the ocean. The entire area is highly prone to landslides; in 2005, the adjacent unincorporated town of La Conchita
was the site of a landslide that killed 10 people. During exceptionally rainy winters, Highway 101 can be cut by landslides.
Native vegetation consists of coastal sage scrub and chaparral. Climate in the area is Mediterranean
, with cool rainy winters and mild summers, the heat being moderated by morning fog and low clouds. About 15 inches of rain fall each year, with slightly more at higher elevations
The Rincon Oil and Gas Processing Facility is adjacent to the oil field, on a hilltop which has been graded flat, about a mile east of Pitas Point. Rather than processing oil from the Rincon field, it receives and processes oil from the offshore Dos Cuadras
and Carpinteria fields, feeding it into the M-143 pipeline which crosses through the Rincon field on the way to Ventura. A single massive 268,000 barrel tank, the feature of the plant visible at the greatest distance, stores oil from the Rincon field prior to shipping it through the pipeline.
The offshore part of the field is mostly in shallow water, and is accessed from Rincon Island, an artificial island about two-thirds of a mile south of Punta Gorda, connected to the mainland by a 3000 feet (914.4 m) causeway. This plank causeway is too narrow for regular vehicular traffic, but contains pipelines to carry oilfield liquids – oil and produced water – as well as natural gas back to the shore, where they are processed at the La Conchita Oil and Gas Processing Facility.
field to the southeast and the huge Ventura Oil Field
beyond the San Miguelito, directly north of the city of Ventura. West of the Rincon field the anticline continues offshore, containing in the Carpinteria offshore field
and the Dos Cuadras field, the source of the notorious 1969 oil spill
. The surface geology of the Rincon field is distinctive, including some of the most landslide-prone terrain in California; much of the surface consists of Holocene sedimentary landslide deposits, greatly prone to renewed landslides.
All of the petroleum-bearing horizons in the Rincon field are in the Pico Formation, a thick sedimentary unit deposited in a shallow marine environment during the Pliocene
, 5.3 to 1.6 million years ago. This formation contains sandstone
s, siltstone
s, and conglomerate
s, sufficiently porous under the anticline
to hold abundant quantities of oil. The field has been divided into three general sections, listed from west to east as the Main Area, Oak Grove, and Padre Canyon areas. Each area has several producing horizons, all in the Pico, and ranging in depth from 3,400 feet in the shallow pool in the western Main Area to the "3rd Grubb" horizon at an average depth of 13,000 feet in the Oak Grove Area. Oil is "medium-grade" throughout the field, ranging in API gravity
of 26 to 30.
-age Pico Formation, encountering a 1,500 psi reservoir pressure.
Other discoveries followed in the next several years. None were spectacular gushers, but they were sufficiently profitable to encourage further drilling. The "Miley" producing horizon was discovered in 1928, and other deeper producing zones within the main area appeared in 1929, with the deepest at 7,800 feet in June 1929. Chanslor-Canfield Midway Oil Corp. discovered the Oak Grove Area in 1931, and Continental Oil Co. found the Padre Canyon area 1936. The deeper zones from both of these areas were not found for another 30 years.
Waterflooding of the field began in 1961, and most zones had active waterflood operations by the end of the 1960s.
Peak production from the entire field was in 1972, when the various producers reported over 4.6 million barrels for the year. This broke a usual pattern for California oil fields, in which the peak production was typically within the first few years after discovery, with a secondary peak occurring after the development of enhanced-recovery technologies in the 1960s.
In 1993, Vintage Petroleum
acquired both the Rincon and adjacent San Miguelito
oil fields from Mobil, Conoco
, and Santa Fe Energy. For operational efficiency, Vintage combined the two adjacent oil fields into a single operating unit. Occidental Petroleum acquired Vintage in 2006, retaining their name and making them a wholly owned subsidiary, and still operates the onshore portion of the field under the Vintage banner.
In 2002, Greka Energy
acquired Rincon Island Limited Partnership, including Rincon Island and a small onshore area of operations alongside U.S. Highway 101. The onshore area contains a cluster of wells directionally drilled into offshore formations. Greka continues to operate these facilities as of 2010.
Oil field
An oil field is a region with an abundance of oil wells extracting petroleum from below ground. Because the oil reservoirs typically extend over a large area, possibly several hundred kilometres across, full exploitation entails multiple wells scattered across the area...
on the coast of southern California, about ten miles northwest of the city of Ventura
Ventura, California
Ventura is the county seat of Ventura County, California, United States, incorporated in 1866. The population was 106,433 at the 2010 census, up from 100,916 at the 2000 census. Ventura is accessible via U.S...
, and about 20 miles east-southeast of the city of Santa Barbara
Santa Barbara, California
Santa Barbara is the county seat of Santa Barbara County, California, United States. Situated on an east-west trending section of coastline, the longest such section on the West Coast of the United States, the city lies between the steeply-rising Santa Ynez Mountains and the Pacific Ocean...
. It is the westernmost onshore field in a series of three fields which follow the Ventura Anticline, an east-west trending feature paralleling the Transverse Ranges
Transverse Ranges
The Transverse Ranges are a group of mountain ranges of southern California, in the Pacific Coast Ranges physiographic region that runs along the Pacific coast from Alaska to Mexico in North America. The Transverse Ranges begin at the southern end of the California Coast Ranges and lie between...
. Discovered in 1927, the oil field is ranked 36th in California by size of recoverable oil reserves, and while mostly depleted – now having, by California Department of Conservation estimates, only about 2.5% of its original oil – it remains productive, with 77 wells active at the beginning of 2008. Oil produced in the field flows through the M-143 pipeline, which parallels U.S. Highway 101 southeast to the Ventura Pump Station, at which point it joins a Tosco pipeline which carries it to Los Angeles area refineries. As of 2009, the primary operators of the field were Occidental Petroleum
Occidental Petroleum
Occidental Petroleum Corporation is a California-based oil and gas exploration and production company with operations in the United States, the Middle East, North Africa, and South America...
for the onshore portion, and Greka Energy
Greka Energy
Greka Energy, currently also known as HVI Cat Canyon Inc. is a private United States oil and gas company operating principally in southern and central California, centered on Santa Barbara County...
for the offshore portion. The offshore part of the field is operated mainly from Rincon Island
Rincon Island, California
Rincon Island is an artificial island located off Rincon Beach in Ventura County, California on public land leased from the California State Lands Commission . The island is situated approximately offshore in of water. The island was constructed in 1958 for the specific purpose of well drilling...
.
Setting
The field occupies a range of steep hills, loosely grouped with the Santa Ynez MountainsSanta 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, and are one of the northernmost mountain ranges in Southern California.-Geography:...
, which attain heights of over 2100 feet at Rincon Mountain and Red Mountain. Highway 101 occupies the narrow terrace at the base of the hills where they meet the Pacific Ocean. Drainage is by ephemeral streams directly into the ocean. The entire area is highly prone to landslides; in 2005, the adjacent unincorporated town of La Conchita
La Conchita, California
La Conchita is a small unincorporated community in western Ventura County, California, on U.S. Route 101 just southeast of the Santa Barbara county line...
was the site of a landslide that killed 10 people. During exceptionally rainy winters, Highway 101 can be cut by landslides.
Native vegetation consists of coastal sage scrub and chaparral. Climate in the area is Mediterranean
Mediterranean climate
A Mediterranean climate is the climate typical of most of the lands in the Mediterranean Basin, and is a particular variety of subtropical climate...
, with cool rainy winters and mild summers, the heat being moderated by morning fog and low clouds. About 15 inches of rain fall each year, with slightly more at higher elevations
The Rincon Oil and Gas Processing Facility is adjacent to the oil field, on a hilltop which has been graded flat, about a mile east of Pitas Point. Rather than processing oil from the Rincon field, it receives and processes oil from the offshore Dos Cuadras
Dos Cuadras Offshore Oil Field
The Dos Cuadras Offshore Oil Field is a large oil and gas field underneath the Santa Barbara Channel about eight miles southeast of Santa Barbara, California. Discovered in 1968, and with a cumulative production of over 260 million barrels of oil, it is the 24th-largest oil field within California...
and Carpinteria fields, feeding it into the M-143 pipeline which crosses through the Rincon field on the way to Ventura. A single massive 268,000 barrel tank, the feature of the plant visible at the greatest distance, stores oil from the Rincon field prior to shipping it through the pipeline.
The offshore part of the field is mostly in shallow water, and is accessed from Rincon Island, an artificial island about two-thirds of a mile south of Punta Gorda, connected to the mainland by a 3000 feet (914.4 m) causeway. This plank causeway is too narrow for regular vehicular traffic, but contains pipelines to carry oilfield liquids – oil and produced water – as well as natural gas back to the shore, where they are processed at the La Conchita Oil and Gas Processing Facility.
Geology
The Rincon field is at the western end of the Ventura Anticline, a long narrow structure rather like the gabled roof on a long house, beneath which petroleum has collected in abundance. Two other similar onshore fields follow the anticline: the San MiguelitoSan Miguelito Oil Field
The San Miguelito Oil Field is a large and currently productive oil field in the hills northwest of the city of Ventura in southern California in the United States. The field is close to the coastline, with U.S...
field to the southeast and the huge Ventura Oil Field
Ventura Oil Field
The Ventura Oil Field is a large and currently productive oil field in the hills immediately north of the city of Ventura in southern California in the United States. It is bisected by California State Route 33, the freeway connecting Ventura to Ojai, and is about eight miles long by two across,...
beyond the San Miguelito, directly north of the city of Ventura. West of the Rincon field the anticline continues offshore, containing in the Carpinteria offshore field
Carpinteria Offshore Oil Field
The Carpinteria Offshore Oil Field is an oil and gas field in Santa Barbara Channel, south of the city of Carpinteria in southern California in the United States...
and the Dos Cuadras field, the source of the notorious 1969 oil spill
1969 Santa Barbara oil spill
The Santa Barbara oil spill occurred in January and February 1969 in the Santa Barbara Channel, near the city of Santa Barbara in Southern California. It was the largest oil spill in United States waters at the time, and now ranks third after the 2010 Deepwater Horizon and 1989 Exxon Valdez spills...
. The surface geology of the Rincon field is distinctive, including some of the most landslide-prone terrain in California; much of the surface consists of Holocene sedimentary landslide deposits, greatly prone to renewed landslides.
All of the petroleum-bearing horizons in the Rincon field are in the Pico Formation, a thick sedimentary unit deposited in a shallow marine environment during the Pliocene
Pliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
, 5.3 to 1.6 million years ago. This formation contains sandstone
Sandstone
Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...
s, siltstone
Siltstone
Siltstone is a sedimentary rock which has a grain size in the silt range, finer than sandstone and coarser than claystones.- Description :As its name implies, it is primarily composed of silt sized particles, defined as grains 1/16 - 1/256 mm or 4 to 8 on the Krumbein phi scale...
s, and conglomerate
Conglomerate (geology)
A conglomerate is a rock consisting of individual clasts within a finer-grained matrix that have become cemented together. Conglomerates are sedimentary rocks consisting of rounded fragments and are thus differentiated from breccias, which consist of angular clasts...
s, sufficiently porous under the anticline
Anticline
In structural geology, an anticline is a fold that is convex up and has its oldest beds at its core. The term is not to be confused with antiform, which is a purely descriptive term for any fold that is convex up. Therefore if age relationships In structural geology, an anticline is a fold that is...
to hold abundant quantities of oil. The field has been divided into three general sections, listed from west to east as the Main Area, Oak Grove, and Padre Canyon areas. Each area has several producing horizons, all in the Pico, and ranging in depth from 3,400 feet in the shallow pool in the western Main Area to the "3rd Grubb" horizon at an average depth of 13,000 feet in the Oak Grove Area. Oil is "medium-grade" throughout the field, ranging in API gravity
API gravity
The American Petroleum Institute gravity, or API gravity, is a measure of how heavy or light a petroleum liquid is compared to water. If its API gravity is greater than 10, it is lighter and floats on water; if less than 10, it is heavier and sinks...
of 26 to 30.
History, production, and operations
The Rincon field was discovered in December 1927, during the tail end of the California oil boom, the period when most of the state's largest fields were discovered and the transportation and refining infrastructure developed. Pan American Petroleum Company drilled the discovery well, Hobson Fee No. 3, to a depth of 2,557 feet into the "Shallow" and "Top" zones of the PliocenePliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
-age Pico Formation, encountering a 1,500 psi reservoir pressure.
Other discoveries followed in the next several years. None were spectacular gushers, but they were sufficiently profitable to encourage further drilling. The "Miley" producing horizon was discovered in 1928, and other deeper producing zones within the main area appeared in 1929, with the deepest at 7,800 feet in June 1929. Chanslor-Canfield Midway Oil Corp. discovered the Oak Grove Area in 1931, and Continental Oil Co. found the Padre Canyon area 1936. The deeper zones from both of these areas were not found for another 30 years.
Waterflooding of the field began in 1961, and most zones had active waterflood operations by the end of the 1960s.
Peak production from the entire field was in 1972, when the various producers reported over 4.6 million barrels for the year. This broke a usual pattern for California oil fields, in which the peak production was typically within the first few years after discovery, with a secondary peak occurring after the development of enhanced-recovery technologies in the 1960s.
In 1993, Vintage Petroleum
Occidental Petroleum
Occidental Petroleum Corporation is a California-based oil and gas exploration and production company with operations in the United States, the Middle East, North Africa, and South America...
acquired both the Rincon and adjacent San Miguelito
San Miguelito Oil Field
The San Miguelito Oil Field is a large and currently productive oil field in the hills northwest of the city of Ventura in southern California in the United States. The field is close to the coastline, with U.S...
oil fields from Mobil, Conoco
Conoco Inc.
Conoco Inc. was an American oil company founded in 1875 as the Continental Oil and Transportation Company. It is now a brand of gasoline and service station in the United States which belongs to the ConocoPhillips Company...
, and Santa Fe Energy. For operational efficiency, Vintage combined the two adjacent oil fields into a single operating unit. Occidental Petroleum acquired Vintage in 2006, retaining their name and making them a wholly owned subsidiary, and still operates the onshore portion of the field under the Vintage banner.
In 2002, Greka Energy
Greka Energy
Greka Energy, currently also known as HVI Cat Canyon Inc. is a private United States oil and gas company operating principally in southern and central California, centered on Santa Barbara County...
acquired Rincon Island Limited Partnership, including Rincon Island and a small onshore area of operations alongside U.S. Highway 101. The onshore area contains a cluster of wells directionally drilled into offshore formations. Greka continues to operate these facilities as of 2010.