“Reserves” are quantities of oil and gas that are already discovered, recoverable, and commercial. Domestic reserves are tracked by the U.S. Energy Information Administration.
The USGS assesses “undiscovered, technically recoverable resources,” which are those that are estimated to exist based on geologic knowledge and theory.
Learn more: USGS Energy Resource Assessments
Related Content
What are the different columns on a USGS oil and gas resource assessment table?
Oil and gas estimates always involve some amounts of uncertainty. To account for this, the USGS presents its assessments of oil and gas potential in the form of a range based on how certain we are that this amount of oil and gas exist. The USGS uses a statistically based process (or model) to calculate the likely range of its estimates. The range of values extends from a 5% or greater likelihood...
What is the difference between the National Petroleum Reserve-Alaska and the Arctic National Wildlife Refuge?
The National Petroleum Reserve-Alaska (NPR-A) is a roughly 23.4 million acre area of Federal land managed by the Bureau of Land Management. It lies in northwest Alaska and borders both the Chukchi Sea to the west and the Beaufort Sea to the north. The NPR-A was originally established in 1923 as a petroleum reserve for the U.S. Navy, then transferred to the Department of the Interior in 1976. The...
Does an assessment of the National Petroleum Reserve-Alaska mean there should or should not be oil and gas production in the Arctic National Wildlife Refuge?
The USGS is an unbiased, non-regulatory science agency, and therefore we do not advocate for or against oil and gas development in any location. The USGS role is to provide scientifically robust, publicly available estimates of potential resources so decision-makers have the best possible information to manage the Nation’s resources. Learn more: About USGS USGS Energy Assessments Alaska Petroleum...
Does the Bakken Formation contain more oil than Saudi Arabia?
Probably not. In 2000, the USGS assessed undiscovered, technically recoverable oil and gas resources in Saudi Arabia at 87 billion barrels (USGS 2000 World Petroleum Assessment) compared to a mean estimate of 4.3 billion barrels of undiscovered, technically recoverable continuous oil in the Bakken and Three Forks formations (USGS 2021 Bakken and Three Forks Assessment). In addition, Saudi Arabia...
How is hydraulic fracturing related to earthquakes and tremors?
Reports of hydraulic fracturing causing felt earthquakes are extremely rare. However, wastewater produced by wells that were hydraulic fractured can cause “induced” earthquakes when it is injected into deep wastewater wells. Wastewater disposal wells operate for longer durations and inject much more fluid than the hydraulic fracturing operations. Wastewater injection can raise pressure levels in...
Assessment of undiscovered conventional oil and gas resources in the eastern Mediterranean area, 2020
Unconventional energy resources: 2015 review. Shale gas and liquids
U.S. Geological Survey assessments of continuous (unconventional) oil and gas resources, 2000 to 2011
The Devonian Marcellus Shale and Millboro Shale
Total Petroleum Systems and Geologic Assessment of Oil and Gas Resources in the Powder River Basin Province, Wyoming and Montana
Undiscovered oil and gas resources underlying the U.S. portions of the Great Lakes, 2005
Mississippian Barnett Shale, Fort Worth basin, north-central Texas: Gas-shale play with multi-trillion cubic foot potential
USGS world petroleum assessment 2000; new estimates of undiscovered oil and natural gas, including reserve growth, outside the United States
Unconventional natural gas resources on U.S. federal lands
World conventional crude oil and natural gas: Identified reserves, undiscovered resources and futures
Production characteristics and resource assessment of the Barnett Shale continuous (unconventional) gas accumulation, Fort Worth Basin, Texas
Related Content
- FAQ
What are the different columns on a USGS oil and gas resource assessment table?
Oil and gas estimates always involve some amounts of uncertainty. To account for this, the USGS presents its assessments of oil and gas potential in the form of a range based on how certain we are that this amount of oil and gas exist. The USGS uses a statistically based process (or model) to calculate the likely range of its estimates. The range of values extends from a 5% or greater likelihood...
What is the difference between the National Petroleum Reserve-Alaska and the Arctic National Wildlife Refuge?
The National Petroleum Reserve-Alaska (NPR-A) is a roughly 23.4 million acre area of Federal land managed by the Bureau of Land Management. It lies in northwest Alaska and borders both the Chukchi Sea to the west and the Beaufort Sea to the north. The NPR-A was originally established in 1923 as a petroleum reserve for the U.S. Navy, then transferred to the Department of the Interior in 1976. The...
Does an assessment of the National Petroleum Reserve-Alaska mean there should or should not be oil and gas production in the Arctic National Wildlife Refuge?
The USGS is an unbiased, non-regulatory science agency, and therefore we do not advocate for or against oil and gas development in any location. The USGS role is to provide scientifically robust, publicly available estimates of potential resources so decision-makers have the best possible information to manage the Nation’s resources. Learn more: About USGS USGS Energy Assessments Alaska Petroleum...
Does the Bakken Formation contain more oil than Saudi Arabia?
Probably not. In 2000, the USGS assessed undiscovered, technically recoverable oil and gas resources in Saudi Arabia at 87 billion barrels (USGS 2000 World Petroleum Assessment) compared to a mean estimate of 4.3 billion barrels of undiscovered, technically recoverable continuous oil in the Bakken and Three Forks formations (USGS 2021 Bakken and Three Forks Assessment). In addition, Saudi Arabia...
How is hydraulic fracturing related to earthquakes and tremors?
Reports of hydraulic fracturing causing felt earthquakes are extremely rare. However, wastewater produced by wells that were hydraulic fractured can cause “induced” earthquakes when it is injected into deep wastewater wells. Wastewater disposal wells operate for longer durations and inject much more fluid than the hydraulic fracturing operations. Wastewater injection can raise pressure levels in...
- Multimedia
- Publications
Assessment of undiscovered conventional oil and gas resources in the eastern Mediterranean area, 2020
Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean resources of 879 million barrels of conventional oil and 286.2 trillion cubic feet of conventional gas in the eastern Mediterranean area.AuthorsChristopher J. Schenk, Tracey J. Mercier, Thomas M. Finn, Cheryl A. Woodall, Kristen R. Marra, Heidi M. Leathers-Miller, Phuong A. Le, Ronald M. DrakeUnconventional energy resources: 2015 review. Shale gas and liquids
Introduction As the source rocks from which petroleum is generated, organic-rich shales have always been considered an important component of petroleum systems. Over the last few years, it has been realized that in some mudrocks, sufficient hydrocarbons remain in place to allow for commercial development, although advanced drilling and completion technology is typically required to access hydroAuthorsNeil S. Fishman, Kent Bowker, Harris Cander, Brian Cardott, Marc Charette, Kenneth Chew, Thomas Chidsey, Russell F. Dubiel, Sven O. Egenhoff, Catherine B. Enomoto, Ursula Hammes, William Harrison, Shu Jiang, Julie A. LeFever, Jock McCracken, Stephen Nordeng, Richard Nyahay, Stephen Sonnenberg, Michael Vanden BergU.S. Geological Survey assessments of continuous (unconventional) oil and gas resources, 2000 to 2011
From 2000 to 2011, the U.S. Geological Survey conducted 139 quantitative assessments of continuous (unconventional) oil and gas accumulations within the United States. This report documents those assessments more fully than previously done by providing detailed documentation of both the assessment input and output. This report also compiles the data into spreadsheet tables that can be more readilyAuthorsThe Devonian Marcellus Shale and Millboro Shale
The recent development of unconventional oil and natural gas resources in the United States builds upon many decades of research, which included resource assessment and the development of well completion and extraction technology. The Eastern Gas Shales Project, funded by the U.S. Department of Energy in the 1980s, investigated the gas potential of organic-rich, Devonian black shales in the AppalaAuthorsDaniel J. Soeder, Catherine B. Enomoto, John A. ChermakTotal Petroleum Systems and Geologic Assessment of Oil and Gas Resources in the Powder River Basin Province, Wyoming and Montana
The U.S. Geological Survey completed an assessment of the undiscovered oil and gas potential of the Powder River Basin in 2006. The assessment of undiscovered oil and gas used the total petroleum system concept, which includes mapping the distribution of potential source rocks and known petroleum accumulations and determining the timing of petroleum generation and migration. Geologically based, itUndiscovered oil and gas resources underlying the U.S. portions of the Great Lakes, 2005
The U.S. Geological Survey (USGS) completed an assessment of the undiscovered oil and gas potential of the U.S. portions of the Appalachian Basin and the Michigan Basin in 2002 and 2004, respectively. Following the assessments of these two basins, oil and gas allocations were assigned to the U.S. portions of the Great Lakes - Lake Superior (Michigan, Minnesota, and Wisconsin), Lake Michigan (IllinAuthorsJames L. Coleman, Christopher S. Swezey, Robert T. Ryder, Ronald R. CharpentierMississippian Barnett Shale, Fort Worth basin, north-central Texas: Gas-shale play with multi-trillion cubic foot potential
The Mississippian Barnett Shale serves as source, seal, and reservoir to a world-class unconventional natural-gas accumulation in the Fort Worth basin of north-central Texas. The formation is a lithologically complex interval of low permeability that requires artificial stimulation to produce. At present, production is mainly confined to a limited portion of the northern basin where the Barnett ShAuthorsScott L. Montgomery, D.M. Jarvie, K.A. Bowker, R. M. PollastroUSGS world petroleum assessment 2000; new estimates of undiscovered oil and natural gas, including reserve growth, outside the United States
Oil and natural gas account for approximately 63 percent of the world’s total energy consumption. The U.S. Geological Survey periodically estimates the amount of oil and gas remaining to be found in the world. Since 1981, each of the last four of these assessments has shown a slight increase in the combined volume of identified reserves and undiscovered resources. The latest assessment estimates tAuthorsUnconventional natural gas resources on U.S. federal lands
No abstract available.AuthorsRobert A. Crovelli, J. W. Schmoker, Vito F. NuccioWorld conventional crude oil and natural gas: Identified reserves, undiscovered resources and futures
This report summarizes, at the petroleum basin level, the United States Geological Survey's World Energy Program 1993 assessment of world conventional oil and gas resources. The maps provided show boundaries of petroleum basins that are referenced by the assessment, as well as, future oil and gas potential. The 'Futures' or future potential of a basin is calculated as the the sum of the IdentifiedAuthorsC.D. Masters, D. H. Root, R. M. TurnerProduction characteristics and resource assessment of the Barnett Shale continuous (unconventional) gas accumulation, Fort Worth Basin, Texas
No abstract available.AuthorsJ. W. Schmoker, J.C. Quinn, R. A. Crovelli, V. F. Nuccio, T.C. Hester - News