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74-414: The Los Angeles City Oil Field is a large oil field north of Downtown Los Angeles . Long and narrow, it extends from immediately south of Dodger Stadium west to Vermont Avenue , encompassing an area of about four miles (6 km) long by a quarter-mile across. Its former productive area amounts to 780 acres (3.2 km). Discovered in 1890, and made famous by Edward Doheny 's successful well in 1892,

148-532: A Ross Dress for Less in the Fairfax District in 1985, caused by an overnight accumulation of methane which had seeped up from the underlying Salt Lake Oil Field , construction over Los Angeles's old oil fields became much more controversial and difficult. The city defined "methane zones" around all oil fields within its limits, and then enacted ordinances to ensure that new and existing structures within these zones were sufficiently ventilated to prevent

222-445: A cap rock) is a fundamental part of the trap that prevents hydrocarbons from further upward migration. A capillary seal is formed when the capillary pressure across the pore throats is greater than or equal to the buoyancy pressure of the migrating hydrocarbons. They do not allow fluids to migrate across them until their integrity is disrupted, causing them to leak. There are two types of capillary seal whose classifications are based on

296-406: A consequence, oil and natural gas are often found together. In common usage, deposits rich in oil are known as oil fields, and deposits rich in natural gas are called natural gas fields. In general, organic sediments buried in depths of 1,000 m to 6,000 m (at temperatures of 60 ° C to 150 °C) generate oil, while sediments buried deeper and at higher temperatures generate natural gas. The deeper

370-407: A few, very large offshore drilling rigs, due to the cost and logistical difficulties in working over water. Rising gas prices in the early 21st century encouraged drillers to revisit fields that previously were not considered economically viable. For example, in 2008 McMoran Exploration passed a drilling depth of over 32,000 feet (9754 m) (the deepest test well in the history of gas production) at

444-656: A gravity higher than 45 API. Gas cycling is the process where dry gas is injected and produced along with condensed liquid. Topanga Canyon Formation The Topanga Canyon Formation ( / t ə ˈ p æ ŋ ɡ ə / ) is a Miocene epoch geologic formation in the Santa Monica Mountains , Simi Hills , Santa Ana Mountains and San Joaquin Hills, in Los Angeles County , Ventura County , and Orange County, southern California . It

518-471: A result of changes in the structure of the subsurface from processes such as folding and faulting , leading to the formation of domes , anticlines , and folds. Examples of this kind of trap are an anticline trap, a fault trap, and a salt dome trap. They are more easily delineated and more prospective than their stratigraphic counterparts, with the majority of the world's petroleum reserves being found in structural traps. Stratigraphic traps are formed as

592-435: A result of lateral and vertical variations in the thickness, texture, porosity, or lithology of the reservoir rock. Examples of this type of trap are an unconformity trap, a lens trap and a reef trap. Hydrodynamic traps are a far less common type of trap. They are caused by the differences in water pressure, that are associated with water flow, creating a tilt of the hydrocarbon-water contact. The seal (also referred to as

666-502: A significantly higher displacement pressure such that the pressure required for tension fracturing is actually lower than the pressure required for fluid displacement—for example, in evaporites or very tight shales. The rock will fracture when the pore pressure is greater than both its minimum stress and its tensile strength then reseal when the pressure reduces and the fractures close. Unconventional (oil & gas) reservoirs are accumulations where oil and gas phases are tightly bound to

740-428: Is an economic benefit worthy of commercial attention. Oil fields may extend up to several hundred kilometers across the surface, meaning that extraction efforts can be large and spread out across the area. In addition to extraction equipment, there may be exploratory wells probing the edges to find more reservoir area, pipelines to transport the oil elsewhere, and support facilities. Oil fields can occur anywhere that

814-402: Is analogous to saying that the oil which can be extracted forms within the source rock itself, as opposed to accumulating under a cap rock. Oil sands are an example of an unconventional oil reservoir. Unconventional reservoirs and their associated unconventional oil encompass a broad spectrum of petroleum extraction and refinement techniques, as well as many different sources. Since the oil

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888-403: Is being pursued at a higher rate because of the scarcity of conventional reservoirs around the world. After the discovery of a reservoir, a petroleum engineer will seek to build a better picture of the accumulation. In a simple textbook example of a uniform reservoir, the first stage is to conduct a seismic survey to determine the possible size of the trap. Appraisal wells can be used to determine

962-452: Is best to manage the gas cap effectively, that is, placing the oil wells such that the gas cap will not reach them until the maximum amount of oil is produced. Also a high production rate may cause the gas to migrate downward into the production interval. In this case, over time the reservoir pressure depletion is not as steep as in the case of solution-based gas drive. In this case, the oil rate will not decline as steeply but will depend also on

1036-426: Is called the stock tank oil initially in place . As a result of studying factors such as the permeability of the rock (how easily fluids can flow through the rock) and possible drive mechanisms, it is possible to estimate the recovery factor, or what proportion of oil in place can be reasonably expected to be produced. The recovery factor is commonly 30–35%, giving a value for the recoverable resources. The difficulty

1110-490: Is contained within the source rock, unconventional reservoirs require that the extracting entity function as a mining operation rather than drilling and pumping like a conventional reservoir. This has tradeoffs, with higher post-production costs associated with complete and clean extraction of oil being a factor of consideration for a company interested in pursuing a reservoir. Tailings are also left behind, increasing cleanup costs. Despite these tradeoffs, unconventional oil

1184-431: Is more accurate to divide the oil industry into three sectors: upstream ( crude oil production from wells and separation of water from oil ), midstream (pipeline and tanker transport of crude oil) and downstream ( refining of crude oil to products, marketing of refined products, and transportation to oil stations). More than 65,000 oil fields are scattered around the globe, on land and offshore. The largest are

1258-640: Is one of many in the Los Angeles Basin. To the west are the still-productive Salt Lake and Beverly Hills fields; to the south is the Los Angeles Downtown Oil Field. Ten miles east-southeast is the Brea-Olinda field , the first to be worked in the region. Even larger fields are still productive in other parts of the basin, such as the giant Wilmington field which stretches from Carson to Long Beach . Terrain in

1332-649: Is shared between Iran and Qatar . The second largest natural gas field is the Urengoy gas field , and the third largest is the Yamburg gas field , both in Russia . Like oil, natural gas is often found underwater in offshore gas fields such as the North Sea , Corrib Gas Field off Ireland , and near Sable Island . The technology to extract and transport offshore natural gas is different from land-based fields. It uses

1406-413: Is that reservoirs are not uniform. They have variable porosities and permeabilities and may be compartmentalized, with fractures and faults breaking them up and complicating fluid flow. For this reason, computer modeling of economically viable reservoirs is often carried out. Geologists, geophysicists, and reservoir engineers work together to build a model that allows simulation of the flow of fluids in

1480-940: Is usually necessary to drill into the Earth's crust, although surface oil seeps exist in some parts of the world, such as the La Brea Tar Pits in California and numerous seeps in Trinidad . Factors that affect the quantity of recoverable hydrocarbons in a reservoir include the fluid distribution in the reservoir, initial volumes of fluids in place, reservoir pressure, fluid and rock properties, reservoir geometry, well type, well count, well placement, development concept, and operating philosophy. Modern production includes thermal , gas injection , and chemical methods of extraction to enhance oil recovery. A virgin reservoir may be under sufficient pressure to push hydrocarbons to

1554-634: The Ghawar Field in Saudi Arabia and the Burgan Field in Kuwait , with more than 66 to 104 billion barrels (9.5×10 m ) estimated in each. In the modern age, the location of oil fields with proven oil reserves is a key underlying factor in many geopolitical conflicts. Natural gas originates by the same geological thermal cracking process that converts kerogen to petroleum. As

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1628-593: The Hollywood Freeway , parallels part of the field to the north, and California State Route 110 , the historic Arroyo Seco Parkway – the first freeway in the United States – cuts directly through the eastern part of the field immediately south of Dodger Stadium. The neighborhoods that contain the field include, from west to east, Koreatown , Westlake , Echo Park , Chinatown , and Elysian Park . Some significant public facilities built directly on

1702-793: The Los Angeles Stock Exchange had to open a separate facility just to deal with oil stocks. By far the most successful entrepreneur on the field, however, was a piano teacher from Kentucky named Emma Summers , soon nicknamed the "Oil Queen of California." She purchased a half-interest in an oil well for $ 700 in the area of the present-day Civic Center, using the proceeds from her piano lessons, and then purchased some others on credit. As her wells became successful, she shrewdly acquired others, forcing other operators out of business, and selling her oil to various local power companies, hotels, and utilities, all while doing her own accounting and continuing to give piano lessons at night. When

1776-527: The Topanga Formation , of Miocene age – no commercial quantities of oil have been found at these great depths. The field is split into three geographic zones, unrelated to the three vertical zones. The Western Area contains seeps that were known prehistorically; it is separated from the Central zone by a fault. The Central Area, the first to be exploited, extends from the fault to approximately

1850-493: The Westlake neighborhood, producing about 3.5 barrels per day (0.56 m/d). The fortunes made during development of the field led directly to the discovery and exploitation of other fields in the Los Angeles Basin. Of the 1,250 wells once drilled on the field, and the forest of derricks that once covered the low hills north of Los Angeles from Elysian Park west, little above-ground trace remains. The Los Angeles City field

1924-560: The aquatic ecosystem , which is usually a sea but might also be a river, lake, coral reef, or algal mat , the formation of an oil or gas reservoir also requires a sedimentary basin that passes through four steps: Timing is also an important consideration; it is suggested that the Ohio River Valley could have had as much oil as the Middle East at one time, but that it escaped due to a lack of traps. The North Sea , on

1998-407: The buoyancy forces driving the upward migration of hydrocarbons through a permeable rock cannot overcome the capillary forces of a sealing medium. The timing of trap formation relative to that of petroleum generation and migration is crucial to ensuring a reservoir can form. Petroleum geologists broadly classify traps into three categories that are based on their geological characteristics:

2072-452: The $ 1,000 to $ 1,500 to drill an oil well, could potentially become rich – especially if they could get their well into production before their neighbors drained the oil reservoir. Within a year of the Doheny well there were 121 wells on the field interspersed with homes and businesses, and the field's cumulative production had reached 100,000 barrels (16,000 m). Well crowding was extreme:

2146-671: The Blackbeard site in the Gulf of Mexico. ExxonMobil 's drill rig there had reached 30,000 feet by 2006, without finding gas, before it abandoned the site. Crude oil is found in all oil reservoirs formed in the Earth's crust from the remains of once-living things. Evidence indicates that millions of years of heat and pressure changed the remains of microscopic plants and animals into oil and natural gas. Roy Nurmi, an interpretation adviser for Schlumberger oil field services company, described

2220-547: The Puente Formation, and are given ordinal numbers: First, Second, and Third zones. In addition to these zones, small pockets of oil have been found throughout the upper part of the Puente. The average depth of the three zones from top to bottom is 900, 1,100, and 1,500 feet. Although wells have been drilled to much greater depths – for example, Seaboard Oil Company of Delaware drilled over 7,500 feet (2,300 m) into

2294-746: The accumulation of explosive levels of methane. Mitigation systems for modern buildings include subsurface barriers, ventilation systems, methane detectors, and alarms. Thousands of buildings in the Los Angeles area have such systems, including the Staples Center and Los Angeles Convention Center . Construction of the Belmont Learning Center, now known as the Edward R. Roybal Learning Center , "the nation's most expensive high school" began in 1988 adjacent to, and partially above,

Los Angeles City Oil Field - Misplaced Pages Continue

2368-410: The actual capacity. Laboratory testing can determine the characteristics of the reservoir fluids, particularly the expansion factor of the oil, or how much the oil expands when brought from the high pressure and high temperature of the reservoir to a "stock tank" at the surface. With such information, it is possible to estimate how many "stock tank" barrels of oil are located in the reservoir. Such oil

2442-673: The area is a thin layer of Pliocene - and Pleistocene -age alluvium and terrace deposits. Structurally the field is a faulted anticline which trends generally east to west, with oil accumulations trapped in sand units dipping south, ending to the north either at a fault – in the eastern part of the field – or at the surface as tar seeps, in the western area. Mechanisms of entrapment include pinchouts and local changes of permeability – forms of stratigraphic traps – and structural traps such as oil-bearing units blockaded by unrelated, impermeable units put there by motion along faults . Three separate producing horizons, or vertical zones, are present in

2516-472: The area of former oilfield operations include Shriners Hospital for Children, St. Vincent Medical Center , Belmont High School , and the Edward R. Roybal Learning Center . Oil in the Los Angeles City field is relatively close to the surface. Every productive deposit has been in a single geologic unit, the shallow Miocene -age Puente Formation . Covering the Puente Formation throughout most of

2590-442: The eastern boundary of the field. By the end of 1897, 270 wells had been drilled into this new area. Cumulative production from the entire field at the end of that year had passed a million barrels, from 551 wells. During the early development of the field, no single firm had a dominant share. Drillers started their own companies, flooding the local stock exchange with shares of start-up oil firms. There were so many of these that

2664-517: The field during the first decades of the 20th century was fuel oil, and it was also sprayed onto the young city's dirt roads to settle the dust. Tar seeps have been known in the area from prehistoric times, and the Native American population of the Los Angeles basin used the tar for waterproofing and other purposes. The Spanish settlers used it for their lamps, as a sealant for roofs, and as grease for wagon wheels. The earliest known well on

2738-465: The field occurred before the formation of regulatory agencies in California, record keeping was sometimes sparse, not only for oil production but for the very existence and location of the wells. R.E. Crowder, writing in 1961, counted 142 wells which likely existed, but could not be located; some may have been dry holes. A more recent survey suggested that up to 300 wells may have been drilled within

2812-486: The field was once the top producing oil field in California, accounting for more than half of the state's oil in 1895. In its peak year of 1901, approximately 200 separate oil companies were active on the field, which is now entirely built over by dense residential and commercial development. As of 2011 only one oil well remains active – behind a fence on South Mountain View Avenue one block east of Alvarado Street in

2886-422: The field, called the "Dryden Well", was a relatively shallow hole hand-dug near the intersection of 3rd Street and Coronado Street in 1857. It produced some heavy oil, tar, and asphaltum during the next 30 years, but the amounts were not recorded. The growing town purchased the product from the well owner to oil the streets. Another early well, this one a failure, was dug to almost 400 feet (120 m) in 1865 near

2960-420: The field. However, it was Edward Doheny and Cannon's well, begun on November 4, 1892, that brought the field instant fame. They had dug a well to 155 feet (47 m), halting because of the accumulation of toxic hydrogen sulfide gas in the hole; however the oil seeps they encountered encouraged them to continue. Doheny brought in a sharpened eucalyptus log and used it as an improvised percussion hammer to deepen

3034-421: The former oil field, and within a methane zone. Soil tests in the early 1990s showed methane at high levels, possibly migrating up from old wellbores (not all of which were mapped, let alone abandoned to modern standards). Construction of the complex continued intermittently, with partial demolition and reconstruction after additional contamination and an earthquake fault were found. The Learning Center eventually

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3108-402: The gas bubbles drive the oil to the surface. The bubbles then reach critical saturation and flow together as a single gas phase. Beyond this point and below this pressure, the gas phase flows out more rapidly than the oil because of its lowered viscosity. More free gas is produced, and eventually the energy source is depleted. In some cases depending on the geology the gas may migrate to the top of

3182-407: The geology of the underlying rock allows, meaning that certain fields can be far away from civilization, including at sea. Creating an operation at an oil field can be a logistically complex undertaking, as it involves the equipment associated with extraction and transportation, as well as infrastructure such as roads and housing for workers. This infrastructure has to be designed with the lifespan of

3256-414: The gigantic redwood oil tanks near Echo Lake ruptured, and crude oil flooded downhill into the lake, catching fire and burning on the water for three days. The lake is now part of Echo Park, within the neighborhood of the same name . Lawlessness was a problem during the boom period as well, with oil thieves draining tanks overnight, stealing tools, and sabotaging wells of competitors. As the boom years of

3330-489: The intersection of Temple and Boylston, but the attempt was abandoned after encountering hydrogen sulfide gas from the oil deposits, which were not far below. More persistent drilling in 1890 by several groups of prospectors, including Maltman and Ruhland, succeeded in establishing production of several barrels of oil a day, and the California Department of Conservation credits these drillers with discovering

3404-562: The intersection of the Hollywood and Pasadena Freeways, and the Eastern Area extends northeast from that intersection. Oil in the field is generally heavy, with API gravity averaging about 14, and ranging overall from 12 to 20. An early assessment by Paul Prutzman (1913) rated the quality of the oil from the field as low, due to the high sulfur content and absence of light fractions suitable for refining. The main use for oil taken from

3478-434: The liquid sections applying extra pressure. This is present in the reservoir if there is more gas than can be dissolved in the reservoir. The gas will often migrate to the crest of the structure. It is compressed on top of the oil reserve, as the oil is produced the cap helps to push the oil out. Over time the gas cap moves down and infiltrates the oil, and the well will produce more and more gas until it produces only gas. It

3552-438: The location of oil-water contact and with it the height of the oil bearing sands. Often coupled with seismic data, it is possible to estimate the volume of an oil-bearing reservoir. The next step is to use information from appraisal wells to estimate the porosity of the rock. The porosity of an oil field, or the percentage of the total volume that contains fluids rather than solid rock, is 20–35% or less. It can give information on

3626-438: The oil and form a secondary gas cap. Some energy may be supplied by water, gas in water, or compressed rock. These are usually minor contributions with respect to hydrocarbon expansion. By properly managing the production rates, greater benefits can be had from solution-gas drives. Secondary recovery involves the injection of gas or water to maintain reservoir pressure. The gas/oil ratio and the oil production rate are stable until

3700-436: The oil field in mind, as production can last many years. Several companies, such as Hill International , Bechtel , Esso , Weatherford International , Schlumberger , Baker Hughes and Halliburton , have organizations that specialize in the large-scale construction of the infrastructure to support oil field exploitation. The term "oilfield" can be used as a shorthand to refer to the entire petroleum industry . However, it

3774-724: The other hand, endured millions of years of sea level changes that successfully resulted in the formation of more than 150 oil fields. Although the process is generally the same, various environmental factors lead to the creation of a wide variety of reservoirs. Reservoirs exist anywhere from the land surface to 30,000 ft (9,000 m) below the surface and are a variety of shapes, sizes, and ages. In recent years, igneous reservoirs have become an important new field of oil exploration, especially in trachyte and basalt formations. These two types of reservoirs differ in oil content and physical properties like fracture connectivity, pore connectivity, and rock porosity . A trap forms when

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3848-406: The placement of the well with respect to the gas cap. As with other drive mechanisms, water or gas injection can be used to maintain reservoir pressure. When a gas cap is coupled with water influx, the recovery mechanism can be highly efficient. Water (usually salty) may be present below the hydrocarbons. Water, as with all liquids, is compressible to a small degree. As the hydrocarbons are depleted,

3922-431: The preferential mechanism of leaking: the hydraulic seal and the membrane seal. A membrane seal will leak whenever the pressure differential across the seal exceeds the threshold displacement pressure, allowing fluids to migrate through the pore spaces in the seal. It will leak just enough to bring the pressure differential below that of the displacement pressure and will reseal. A hydraulic seal occurs in rocks that have

3996-429: The pressure. As the reservoir depletes, the pressure falls below the bubble point , and the gas comes out of solution to form a gas cap at the top. This gas cap pushes down on the liquid helping to maintain pressure. This occurs when the natural gas is in a cap below the oil. When the well is drilled the lowered pressure above means that the oil expands. As the pressure is reduced it reaches bubble point, and subsequently

4070-477: The price of oil peaked around $ 1.80 a barrel, she controlled about half of the wells on the central portion of the field. In 1903 the boom briefly turned to bust as the price of oil dropped to only fifteen cents a barrel, due to abundant oil flooding the market from the Los Angeles field and others just opening up both in the Los Angeles basin and in the San Joaquin Valley. The peak year for the field

4144-485: The process as follows: Plankton and algae, proteins and the life that's floating in the sea, as it dies, falls to the bottom, and these organisms are going to be the source of our oil and gas. When they're buried with the accumulating sediment and reach an adequate temperature, something above 50 to 70 °C they start to cook. This transformation, this change, changes them into the liquid hydrocarbons that move and migrate, will become our oil and gas reservoir. In addition to

4218-491: The reduction in pressure in the reservoir allows the water to expand slightly. Although this unit expansion is minute, if the aquifer is large enough this will translate into a large increase in volume, which will push up on the hydrocarbons, maintaining pressure. With a water-drive reservoir, the decline in reservoir pressure is very slight; in some cases, the reservoir pressure may remain unchanged. The gas/oil ratio also remains stable. The oil rate will remain fairly stable until

4292-408: The reservoir pressure drops below the bubble point when critical gas saturation is reached. When the gas is exhausted, the gas/oil ratio and the oil rate drops, the reservoir pressure has been reduced, and the reservoir energy is exhausted. In reservoirs already having a gas cap (the virgin pressure is already below bubble point), the gas cap expands with the depletion of the reservoir, pushing down on

4366-409: The reservoir, leading to an improved estimate of the recoverable resources. Reserves are only the part of those recoverable resources that will be developed through identified and approved development projects. Because the evaluation of reserves has a direct impact on the company or the asset value, it usually follows a strict set of rules or guidelines. To obtain the contents of the oil reservoir, it

4440-410: The rock fabric by strong capillary forces, requiring specialised measures for evaluation and extraction. Unconventional reservoirs form in completely different ways to conventional reservoirs, the main difference being that they do not have "traps". This type of reservoir can be driven in a unique way as well, as buoyancy might not be the driving force for oil and gas accumulation in such reservoirs. This

4514-419: The rocks have high porosity and low permeability, which keeps the hydrocarbons trapped in place, therefore not requiring a cap rock . Reservoirs are found using hydrocarbon exploration methods. An oil field is an area of accumulated liquid petroleum underground in multiple (potentially linked) reservoirs, trapped as it rises to impermeable rock formations. In industrial terms, an oil field implies that there

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4588-410: The source, the "drier" the gas (that is, the smaller the proportion of condensates in the gas). Because both oil and natural gas are lighter than water, they tend to rise from their sources until they either seep to the surface or are trapped by a non-permeable stratigraphic trap. They can be extracted from the trap by drilling. The largest natural gas field is South Pars/Asalouyeh gas field, which

4662-454: The structural trap, the stratigraphic trap, and the far less common hydrodynamic trap . The trapping mechanisms for many petroleum reservoirs have characteristics from several categories and can be known as a combination trap. Traps are described as structural traps (in deformed strata such as folds and faults) or stratigraphic traps (in areas where rock types change, such as unconformities, pinch-outs and reefs). Structural traps are formed as

4736-452: The surface. As the fluids are produced, the pressure will often decline, and production will falter. The reservoir may respond to the withdrawal of fluid in a way that tends to maintain the pressure. Artificial drive methods may be necessary. This mechanism (also known as depletion drive) depends on the associated gas of the oil. The virgin reservoir may be entirely semi-liquid but will be expected to have gaseous hydrocarbons in solution due to

4810-453: The town lots were often only 50' by 150', and sometimes contained as many as four wells. By the end of 1895, the field was producing 2,000 barrels (320 m) of oil a day, had produced 750,000 barrels (119,000 m) in the preceding year, and accounted for sixty percent of the state's oil production. But it was still expanding: in 1896 a new well found oil east of the fault zone near Sisters Hospital which had previously been considered to be

4884-512: The vicinity of the Los Angeles City field includes gently rolling hills cut by ravines draining south. Elevations range from around 250 to 500 feet (150 m) above sea level, with the highest elevations in Elysian Park near Dodger Stadium. Urban development is dense in the part of Los Angeles containing the field's former productive area, with numerous apartment blocks mixed with commercial and light industrial structures. U.S. Highway 101,

4958-564: The vicinity of the oil field but abandoned without a trace. By 1961 most of the oil field was dedicated to redevelopment as a residential area, under the auspices of the Los Angeles Urban Renewal Association. At this time, 93 wells still remained active in the field, run by 22 separate companies. One by one the wells have been abandoned, with the one remaining well quietly pumping behind a fence on South Mountain View Avenue. After an explosion which leveled

5032-407: The water begins to be produced along with the oil, the recovery rate may become uneconomical owing to the higher lifting and water disposal costs. If the natural drives are insufficient, as they very often are, then the pressure can be artificially maintained by injecting water into the aquifer or gas into the gas cap. The force of gravity will cause the oil to move downward of the gas and upward of

5106-431: The water reaches the well. In time, the water cut will increase, and the well will be watered out. The water may be present in an aquifer (but rarely one replenished with surface water ). This water gradually replaces the volume of oil and gas that is produced out of the well, given that the production rate is equivalent to the aquifer activity. That is, the aquifer is being replenished from some natural water influx. If

5180-442: The water. If vertical permeability exists then recovery rates may be even better. These occur if the reservoir conditions allow the hydrocarbons to exist as a gas. Retrieval is a matter of gas expansion. Recovery from a closed reservoir (i.e., no water drive) is very good, especially if bottom hole pressure is reduced to a minimum (usually done with compressors at the wellhead). Any produced liquids are light-colored to colorless, with

5254-400: The well, and shortly afterwards they punctured an oil reservoir, and began producing about seven barrels a day. While hardly a gusher, their first well at the corner of Colton and Patton Streets was in the middle of an area of hundreds of small town lots that had been sold in a land boom of 1887. Since there were no regulations in California on well spacing at this time, anyone with a lot, and

5328-401: Was 1901, during which 1,150 active wells pumped over 1.8 million barrels (290,000 m). Over 200 separate companies were in operation on the field at this time. Of these, the largest were Union Consolidated Crude Oil Company, L.A. Terminal & Transport, and Westlake Oil Company. Edward A. Clampitt , an eastern businessman who had come to Los Angeles to make a fortune in the oil industry,

5402-403: Was also one of the principal operators in the first decade of the 20th century. Production declined quickly after the peak; there were simply too many wells draining a reservoir of limited capacity and pressure, and less and less oil was able to be profitably extracted. After 1915 only two new wells were drilled on the field. The early years on the field were not without mishap. In 1907, one of

5476-563: Was completed at a cost of $ 377 million, not far from the area that was the field's center of operations 100 years before. 34°03′57″N 118°16′04″W  /  34.0659°N 118.2677°W  / 34.0659; -118.2677 Oil field Reservoirs are broadly classified as conventional and unconventional reservoirs. In conventional reservoirs, the naturally occurring hydrocarbons, such as crude oil ( petroleum ) or natural gas , are trapped by overlying rock formations with lower permeability , while in unconventional reservoirs

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