Saticoy Oil Field
Encyclopedia
The Saticoy Oil Field is an oil and gas field in Ventura County, California
, in the United States. The field is a long narrow band paralleling the Santa Clara River
near the town of Saticoy
. Discovered in 1955, it is one of the smaller but productive fields found in the region after most of the large fields had already been operational for decades. At the beginning of 2009 it still contained an estimated 387000 barrels (61,528,083.2 l) of recoverable oil out of its original 23.5 million, and had 15 wells remaining in operation. Vintage Production, a subsidiary of Occidental Petroleum
, was the primary operator on the field as of 2009. p. 101, 166
parallels the field for its entire length, about one-half mile to the northwest. The large South Mountain Oil Field
is adjacent on the northeast, and the Oxnard Oil Field
is on the south, across the river and on the other side of U.S. Highway 101.
Land use in the vicinity of the field is predominantly agricultural, with oil wells and associated production infrastructure interspersed between working agricultural fields and orchards. Climate in the region is Mediterranean
, with cool, rainy winters and warm, rainless summers, in which the heat is moderated by frequent morning coastal low clouds and fog. Annual precipitation is around 15 inches, almost all in the winter, and all in the form of rain. The mean annual temperature is 56 °F (13.3 °C) to 60 °F (15.6 °C); freezes occur rarely. Elevations on the field range from about 140 to 220 ft (42.7 to 67.1 ) above sea level. As it is in the Santa Clara River floodplain it is mostly flat, with runoff going directly into the adjacent Santa Clara River which flows west toward its outlet into the Pacific Ocean between Oxnard and Ventura.
that occurred during the late Pliocene
. Within the Ventura Basin are some of the richest agricultural fields in California, made possible by the thick alluvial
topsoil left by tens of thousands of years of floods from the area's river systems. The basin is filled with sedimentary
layers, and cut through from northeast to southwest by the Oak Ridge Fault.
In the Saticoy field, oil is trapped both in pinchouts of updipping permeable sedimentary units within units of lesser permeability, and in sedimentary units which end abruptly at the Oak Ridge Thrust Fault; oil migrating upwards within permeable units, in this case, encounters an impermeable barrier of rock placed there by the fault. Horizontally, the fault defines the course of the Santa Clara River and the northern base of the hills south of the river (including South Mountain), and is part of the fault complex responsible for the 1994 Northridge earthquake. The fault bounds the field on the southeast; many of the oil-bearing units have been deformed so as to be aligned almost vertically, especially in the lower zones. The sedimentary units are predominantly turbidite
s, and are of Pleistocene
and Pliocene age. From the top down, the units are the Pleistocene Santa Barbara Formation, which contains the producing horizon labeled the "Upper F Zone"; and the Upper Pliocene Pico Sand, which contains the horizons labeled "Lower F Zone", "G Zone", "H Zone", "I Zone", "J Zone", and "K Zone." Most of the oil is between 6000 and 9000 ft (1,828.8 and 2,743.2 ) below ground surface.
Oil is of medium gravity and low sulfur content throughout, varying little between the different producing horizons. API gravity
varies from 30 to 36. The shallowest producing formation, the Upper F Zone, has an average depth of 6350 feet (1,935.5 m) below ground surface, and the deepest, the K, has an average depth of 9035 feet (2,753.9 m).
As production began its inevitable decline, Shell commenced waterflooding
operations to increase reservoir pressure and dispose of produced water. Waterflooding ran from 1963 to 1968 in the G, H, I, and J zones.
Shell held most of the field until 1984, at which time they sold it to Sage Energy. This was a period during which many of the major oil companies were divesting their operations in the onshore coastal portions of California, selling them to smaller independent operators, in order to focus on more profitable opportunities overseas. Sage held the field until 1990, at which time they sold it to Whiting Petroleum Corp; Whiting sold some active wells to Crimson Resource Management Corp. in 1994. Crimson ran the field until 2002, at which time they sold their 41 remaining wells to Bentley-Simonson, who held it until April 2005, selling to Plains Exploration & Production
, who operated the declining field for slightly more than a year, selling the 14 remaining active wells to their present operator, Vintage Production, in October 2006.
As of 2010, there were 15 wells remaining on the field, 14 active and operated by Vintage. The one other, owned by Ibsen Resource Management, Inc., had been idled. The 14 Vintage wells were each producing oil at an average rate of 8.1 oilbbl/d.
Ventura County, California
Ventura County is a county in the southern part of the U.S. state of California. It is located on California's Pacific coast. It is often referred to as the Gold Coast, and has a reputation of being one of the safest populated places and one of the most affluent places in the country...
, in the United States. The field is a long narrow band paralleling the Santa Clara River
Santa Clara River (California)
The Santa Clara River is approximately long, located in southern California in the United States. It drains an area of the coastal mountains north of Los Angeles. The Santa Clara is one of the largest river systems along the coast of Southern California and one of only a few remaining river...
near the town of Saticoy
Saticoy, California
Saticoy is an unincorporated town and census-designated place in Ventura County, California. It lies in the Santa Clara River Valley, south of the intersection of Wells Road and the Santa Paula Freeway, on the east side of Ventura, and north of the Santa Clara River at the head of the delta...
. Discovered in 1955, it is one of the smaller but productive fields found in the region after most of the large fields had already been operational for decades. At the beginning of 2009 it still contained an estimated 387000 barrels (61,528,083.2 l) of recoverable oil out of its original 23.5 million, and had 15 wells remaining in operation. Vintage Production, a subsidiary of 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...
, was the primary operator on the field as of 2009. p. 101, 166
Setting
The field is long and narrow, exactly following the Oak Ridge Fault which also defines the alignment of the Santa Clara River, running from northeast to southwest. The field is approximately four miles long by one-quarter mile across, amounting to 640 productive acres total, mostly on the northwest side of the Santa Clara River. California State Route 126California State Route 126
State Route 126 is a highway in Ventura and Los Angeles counties, California. The route runs from U.S. Route 101 in Ventura to Interstate 5 in Santa Clarita...
parallels the field for its entire length, about one-half mile to the northwest. The large South Mountain Oil Field
South Mountain Oil Field
The South Mountain Oil Field is a large and productive oil field in Ventura County, California, in the United States, in and adjacent to the city of Santa Paula. Discovered in 1916, and having a cumulative production of over of oil, it is the 37th largest oil field in California and the second...
is adjacent on the northeast, and the Oxnard Oil Field
Oxnard Oil Field
The Oxnard Oil Field is a large and currently productive oil field in and adjacent to the city of Oxnard, in Ventura County, California in the United States. Its conventional oil reserves are close to exhaustion, with only an estimated one percent of the original oil recoverable with current...
is on the south, across the river and on the other side of U.S. Highway 101.
Land use in the vicinity of the field is predominantly agricultural, with oil wells and associated production infrastructure interspersed between working agricultural fields and orchards. Climate in the region 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 warm, rainless summers, in which the heat is moderated by frequent morning coastal low clouds and fog. Annual precipitation is around 15 inches, almost all in the winter, and all in the form of rain. The mean annual temperature is 56 °F (13.3 °C) to 60 °F (15.6 °C); freezes occur rarely. Elevations on the field range from about 140 to 220 ft (42.7 to 67.1 ) above sea level. As it is in the Santa Clara River floodplain it is mostly flat, with runoff going directly into the adjacent Santa Clara River which flows west toward its outlet into the Pacific Ocean between Oxnard and Ventura.
Geology
The Saticoy field is within the Ventura Basin Province of southern California. Geologically, this area is part of a structural downwarpDepression (geology)
A depression in geology is a landform sunken or depressed below the surrounding area. Depressions may be formed by various mechanisms.Structural or tectonic related:...
that occurred during the late 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...
. Within the Ventura Basin are some of the richest agricultural fields in California, made possible by the thick alluvial
Alluvium
Alluvium is loose, unconsolidated soil or sediments, eroded, deposited, and reshaped by water in some form in a non-marine setting. Alluvium is typically made up of a variety of materials, including fine particles of silt and clay and larger particles of sand and gravel...
topsoil left by tens of thousands of years of floods from the area's river systems. The basin is filled with sedimentary
Sedimentary rock
Sedimentary rock are types of rock that are formed by the deposition of material at the Earth's surface and within bodies of water. Sedimentation is the collective name for processes that cause mineral and/or organic particles to settle and accumulate or minerals to precipitate from a solution....
layers, and cut through from northeast to southwest by the Oak Ridge Fault.
In the Saticoy field, oil is trapped both in pinchouts of updipping permeable sedimentary units within units of lesser permeability, and in sedimentary units which end abruptly at the Oak Ridge Thrust Fault; oil migrating upwards within permeable units, in this case, encounters an impermeable barrier of rock placed there by the fault. Horizontally, the fault defines the course of the Santa Clara River and the northern base of the hills south of the river (including South Mountain), and is part of the fault complex responsible for the 1994 Northridge earthquake. The fault bounds the field on the southeast; many of the oil-bearing units have been deformed so as to be aligned almost vertically, especially in the lower zones. The sedimentary units are predominantly turbidite
Turbidite
Turbidite geological formations have their origins in turbidity current deposits, which are deposits from a form of underwater avalanche that are responsible for distributing vast amounts of clastic sediment into the deep ocean.-The ideal turbidite sequence:...
s, and are of Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
and Pliocene age. From the top down, the units are the Pleistocene Santa Barbara Formation, which contains the producing horizon labeled the "Upper F Zone"; and the Upper Pliocene Pico Sand, which contains the horizons labeled "Lower F Zone", "G Zone", "H Zone", "I Zone", "J Zone", and "K Zone." Most of the oil is between 6000 and 9000 ft (1,828.8 and 2,743.2 ) below ground surface.
Oil is of medium gravity and low sulfur content throughout, varying little between the different producing horizons. 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...
varies from 30 to 36. The shallowest producing formation, the Upper F Zone, has an average depth of 6350 feet (1,935.5 m) below ground surface, and the deepest, the K, has an average depth of 9035 feet (2,753.9 m).
History, production and operations
Shell Oil Co. drilled the discovery well for the field in May 1955, reaching a depth of 12,020 feet. Development of the Saticoy field was unusual in that the deepest producing horizons, the J and K, were the first to be discovered. All of the rest – F, G, H, and I – had been found by Shell by August 1956, and development of the field was quick after that. The field reached peak production in 1958 at 2.8 Moilbbl of oil per year.As production began its inevitable decline, Shell commenced waterflooding
Water injection (oil production)
Water injection refers to the method in oil industry where water is injected back into the reservoir, usually to increase pressure and thereby stimulate production. Water injection wells can be found both on- and offshore, to increase oil recovery from an existing reservoir...
operations to increase reservoir pressure and dispose of produced water. Waterflooding ran from 1963 to 1968 in the G, H, I, and J zones.
Shell held most of the field until 1984, at which time they sold it to Sage Energy. This was a period during which many of the major oil companies were divesting their operations in the onshore coastal portions of California, selling them to smaller independent operators, in order to focus on more profitable opportunities overseas. Sage held the field until 1990, at which time they sold it to Whiting Petroleum Corp; Whiting sold some active wells to Crimson Resource Management Corp. in 1994. Crimson ran the field until 2002, at which time they sold their 41 remaining wells to Bentley-Simonson, who held it until April 2005, selling to Plains Exploration & Production
Plains Exploration & Production
Plains Exploration & Production, commonly known by its New York Stock Exchange ticker symbol , is a U.S. petroleum company based in Houston, Texas. A spin-off from Plains Resources, Inc., the company was founded in 2002. Its operations, as of 2009, were all in North America, including California,...
, who operated the declining field for slightly more than a year, selling the 14 remaining active wells to their present operator, Vintage Production, in October 2006.
As of 2010, there were 15 wells remaining on the field, 14 active and operated by Vintage. The one other, owned by Ibsen Resource Management, Inc., had been idled. The 14 Vintage wells were each producing oil at an average rate of 8.1 oilbbl/d.