Within the

petroleum industry The petroleum industry, also known as the oil industry or the oil patch, includes the global processes of exploration, extraction, refining, transportation (often by oil tankers and pipelines), and marketing of petroleum products. The large ...

, proved crude

oil reserves An oil is any nonpolar chemical substance that is composed primarily of hydrocarbons and is hydrophobic (does not mix with water) & lipophilic (mixes with other oils). Oils are usually flammable and surface active. Most oils are unsaturate ...

and lease condensate in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

was of crude oil as of the end of 2021, excluding the Strategic Petroleum Reserve. In 2012, the Energy Information Administration using data compiled by the United States Geolgical Survey under the Department of the Interior estimated US undiscovered, technically recoverable oil resources to be an additional 198 billion barrels.

History

Over 1 million exploratory and developmental crude oil wells have been drilled in the US since 1949 to estimate the undiscovered, technically recoverable oil in the United States. The last comprehensive National Assessment was completed in 1995. Since 2000 the

USGS The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, a ...

has been re-assessing basins of the U.S. that are considered to be priorities for oil and gas resources; re-assessing 22, and has plans to re-assess 10 more basins. These 32 basins represent about 97% of the discovered and undiscovered oil and gas resources of the United States. The three areas considered to hold the most oil are the coastal plain (1002) area of ANWR, the National Petroleum Reserve of Alaska, and the Bakken Formation.

Proved reserves major discoveries

In 1970, supergiant Prudhoe Bay field was found in Alaska.

Reserves to Production ratio

The reserves-to-production ratio (R/P) was 11.08 years in 1970. It hit a trough of 8.49 years in 1986 as oil pumped through the Alaska pipeline began to peak. R/P was 11.26 years in 2007.

Production impacts

In 1970, local Peak production was per day in November 1970.U.S. Field Production of Crude Oil
/ref>Total production of crude oil from 1970 through 2006 was , or roughly five and a half times the proved reserves over the same timeframe when taking into account the decreasing proved reserves. When global oil prices (~US$147.50) peaked in summer 2008 many petroleum

oil extraction Petroleum is a fossil fuel that can be drawn from beneath the earth's surface. Reservoirs of petroleum was formed through the mixture of plants, algae, and sediments in shallow seas under high pressure. Petroleum is mostly recovered from oil dri ...

projects were brought online, allowing annual production to steadily increase, with one year of decline in 2020 attributed to the COVID pandemic. In 2012 the oil production of the USA increased by 800,000 barrels per day, the highest ever recorded increase in one year since oil drilling began in 1859. In April 2013, US crude production was at a more than 20-year high, aided by the

shale gas Shale gas is an unconventional natural gas that is found trapped within shale formations. Since the 1990s a combination of horizontal drilling and hydraulic fracturing has made large volumes of shale gas more economical to produce, and some ...

and

tight oil Tight oil (also known as shale oil, shale-hosted oil or light tight oil, abbreviated LTO) is light crude oil contained in unconventional petroleum-bearing formations of low permeability, often shale or tight sandstone. Economic production from ...

boom; with production near 7.2 million barrels per day. In November 2019, peak production was per day. With increased production, experts think that the USA could pass Saudi Arabia as the largest oil producer.

Consumption and net imports

Consuming less or importing more oil prolongs the useful life of existing oil reserves. Between 1970 and 2007, due to declining production and increasing demand, net US imports of oil and petroleum products increased from in 1970 to in 2007, before declining as domestic production ramped up. In 2007 the largest net suppliers(importers) of petroleum products were Canada and Mexico, which supplied In 2011, the US consumed 18.8 million barrels of petroleum products per day, and imported a net 8.4 million barrels per day; the EIA reported the United States "Dependence on Net Petroleum Imports" in 2011 as 45% accouting for nearly 50% of the US trade deficit in 2011. For a brief period during 2008-2009 the USA became a net exporter of refined oil products.

Strategic Petroleum Reserve

The United States maintains a Strategic Petroleum Reserve at four sites on the

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United ...

, with a total capacity of of crude oil. The maximum total withdrawal capability from the United States Strategic Petroleum Reserve is per day. This is roughly 32% of US oil imports, or 75% of imports from OPEC.

Conventional Prospective resources

Onshore

The

United States Geological Survey The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, ...

(USGS) under the Department of the Interiorestimates undiscovered technically recoverable crude oil onshore in United States to be

Arctic

In 1998, the USGS estimated that the 1002 area of the

Arctic National Wildlife Refuge The Arctic National Wildlife Refuge (ANWR or Arctic Refuge) is a national wildlife refuge in northeastern Alaska, United States on traditional Gwich'in lands. It consists of in the Alaska North Slope region. It is the largest national wildli ...

contains a total of between 5.7 and of undiscovered, technically recoverable oil, with a mean estimate of , of which falls within the Federal portion of the ANWR 1002 Area. In May 2008 the EIA used this assessment to estimate the potential cumulative production of the 1002 area of ANWR to be a maximum of from 2018 to 2030. This estimate is a best case scenario of technically recoverable oil during the area's primary production years if legislation were passed in 2008 to allow drilling. A 2002 assessment concluded that the

National Petroleum Reserve–Alaska The National Petroleum Reserve in Alaska (NPRA) is an area of land on the Alaska North Slope owned by the United States federal government and managed by the Department of the Interior, Bureau of Land Management (BLM). It lies to the west of the ...

contains between 6.7 and of oil, with a mean (expected) value of . The quantity of undiscovered oil beneath Federal lands (excluding State and Native areas) is estimated to range between 5.9 and 13.2 BBO, with a mean value of 9.3 BBO. Most oil accumulations are expected to be of moderate size, on the order of 30 to each. Large accumulations like the

Prudhoe Bay oil field Prudhoe Bay Oil Field is a large oil field on Alaska's North Slope. It is the largest oil field in North America, covering and originally containing approximately of oil.

(whose ultimate recovery is approximately ), are not expected to occur. The volumes of undiscovered, technically recoverable oil estimated for NPRA are similar to the volumes estimated for ANWR. However, because of differences in accumulation sizes (the ANWR study area is estimated to contain more accumulations in larger size classes) and differences in assessment area (the NPRA study area is more than 12 times larger than the ANWR study area), economically recoverable resources are different at low oil prices. But at market prices above $40 per barrel, estimates of economically recoverable oil for NPRA are similar to ANWR.

Tight oil

In April 2008, the USGS released a report giving a new resource assessment of the Bakken Formation underlying portions of Montana and North Dakota. The USGS believes that with new

horizontal drilling Directional drilling (or slant drilling) is the practice of drilling non-vertical bores. It can be broken down into four main groups: oilfield directional drilling, utility installation directional drilling, directional boring (horizontal dir ...

technology there is somewhere between of undiscovered, technically recoverable oil in this formation that was initially discovered in 1951. If accurate, this reassessment would make it the largest "continuous" oil accumulation (The USGS uses "continuous" to describe accumulations requiring extensive artificial fracturing to allow the oil to flow to the borehole) ever discovered in the U.S. The formation is estimated to contain significantly more—figures in excess of have been reported—but it is yet uncertain how much of this oil is recoverable using current technology. In 2011, Harold Hamm claimed that the recoverable share may reach ; this would mean that Bakken contains more extractable petroleum than all other known oil fields in the country, combined.

Offshore

The

Minerals Management Service The Minerals Management Service (MMS) was an agency of the United States Department of the Interior that managed the nation's natural gas, oil and other mineral resources on the outer continental shelf (OCS). Due to perceived conflict of inter ...

(MMS) estimates the Federal

Outer Continental Shelf The Outer Continental Shelf (OCS) is a feature of the geography of the United States. The OCS is the part of the internationally recognized continental shelf of the United States which does not fall under the jurisdictions of the individual U. ...

(OCS) contains between of undiscovered technically recoverable crude oil, with a mean estimate of . The Gulf of Mexico OCS ranks first with a mean estimate of , followed by Alaska OCS with . At $80/bbl crude prices, the MMS estimates that are economically recoverable. As of 2008, a total of about of the OCS are off-limits to leasing and development. The moratoria and presidential withdrawal cover about 85 percent of OCS area offshore the lower 48 states. The MMS estimates that the resources in OCS areas currently off limits to leasing and development total (mean estimate).

Unconventional prospective resources

Oil Shale Oil shale is an organic-rich fine-grained sedimentary rock containing kerogen (a solid mixture of organic chemical compounds) from which liquid hydrocarbons can be produced. In addition to kerogen, general composition of oil shales constitut ...
prospective resources

Oil shale

The United States has the largest known deposits of

oil shale Oil shale is an organic-rich fine-grained sedimentary rock containing kerogen (a solid mixture of organic chemical compounds) from which liquid hydrocarbons can be produced. In addition to kerogen, general composition of oil shales constitut ...

in the world, according to the Bureau of Land Management and holds an estimated of potentially recoverable oil. Oil shale does not actually contain oil, but a waxy oil precursor known as

kerogen Kerogen is solid, insoluble organic matter in sedimentary rocks. Comprising an estimated 1016 tons of carbon, it is the most abundant source of organic compounds on earth, exceeding the total organic content of living matter 10,000-fold. It ...

. There is significant commercial production of oil from oil shale in the United States in

North Dakota North Dakota () is a U.S. state in the Upper Midwest, named after the indigenous Dakota Sioux. North Dakota is bordered by the Canadian provinces of Saskatchewan and Manitoba to the north and by the U.S. states of Minnesota to the east, So ...

and

Montana Montana () is a state in the Mountain West division of the Western United States. It is bordered by Idaho to the west, North Dakota and South Dakota to the east, Wyoming to the south, and the Canadian provinces of Alberta, British Columb ...

. Oil-bearing shales in

and

are producing increasing amounts of oil. As of April 2013, US crude production was at a more than 20-year high, since the

and

boom; production was near 7.2 million barrels per day.

Oil sands

There are significant volumes of heavy oil in the

oil sands Oil sands, tar sands, crude bitumen, or bituminous sands, are a type of unconventional petroleum deposit. Oil sands are either loose sands or partially consolidated sandstone containing a naturally occurring mixture of sand, clay, and wate ...

of northeast

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to it ...

. There has yet to be any significant production from these deposits.

References

{{DEFAULTSORT:Oil Reserves In The United States Fossil fuels in the United States Geology of the United States