USGS Energy Resources Program provides periodic assessments of the oil and natural gas endowment of the United States and the World. This website provides access to new, prioritized, assessment results and supporting data for the United States, as part of the Energy Policy and Conservation Act (EPCA).
Assessment Overview
The USGS assesses potential for undiscovered oil and gas resources in priority geologic provinces in the United States. This website highlights conventional and unconventional (continuous) oil and gas assessments.
Summary of Continuous Assessments
This applications shows maps and tables of all continuous assessments in the United States.
Recent Assessments
Below are the latest US Assessments:
National Oil and Gas Assessment Methodology
The U.S. Geological Survey Energy Resources Program assesses the potential for undiscovered oil and gas resources in priority geologic provinces in the United States and around the world (click here for information about World Oil and Gas Assessments). Two methodologies are used by the USGS; one for assessing conventional oil and gas resources and one for assessing unconventional (continuous) oil and gas resources (such as shale gas and coalbed gas). USGS publications detailing and explaining the conventional and continuous assessment methodologies are provided below. These methodologies have been subjected to rigorous peer reviews by non federal panels, and the two panel reports are provided on this page.
Conventional Resources
USGS Reports
U.S. Geological Survey Assessment Concepts for Conventional Petroleum Accumulations
By James W. Schmoker and T.R. Klett
U.S. Geological Survey Input-Data Form and Operational Procedure for the Assessment of Conventional Petroleum Accumulations
By T.R. Klett, James W. Schmoker, and Ronald R. Charpentier
A Monte Carlo Simulation Method for the Assessment of Undiscovered, Conventional Oil and Gas
By Ronald R. Charpentier and T.R. Klett
Continuous Resources
USGS Reports
U.S. Geological Survey Assessment Concepts for Continuous Petroleum Accumulations
By James W. Schmoker
U.S. Geological Survey Input-Data Form and Operational Procedure for the Assessment Of Continuous Petroleum Accumulations, 2002
By T.R. Klett and James W. Schmoker
Analytic Resource Assessment Method for Continuous Petroleum Accumulations—The ACCESS Assessment Method
By Robert A. Crovelli
FORSPAN Model Users Guide
By T.R. Klett, and Ronald R. Charpentier
Methodology Revisions
Improved USGS methodology for assessing continuous petroleum resources.
Charpentier, R.R., and Cook, T.A.
Applying Probabilistic Well-Performance Parameters to Assessments of Shale-Gas Resources
By Ronald R. Charpentier and Troy Cook
Assembling Probabilistic Performance Parameters of Shale-Gas Wells
By Cook, Troy, and Charpentier, R.R.
USGS Methodology for Assessing Continuous Petroleum Resources
By Ronald R. Charpentier and Troy Cook
New U.S. Geological Survey Method for the Assessment of Reserve Growth
By Timothy R. Klett, Emil D. Attanasi, Ronald R. Charpentier, Troy A. Cook, Philip A. Freeman, Donald L. Gautier, Phuong A. Le, Robert T. Ryder, Christopher J. Schenk, Marilyn E. Tennyson, and Mahendra K. Verma (Reserve Growth Assessment Team)
Variability of Distributions of Well-Scale Estimated Ultimate Recovery for Continuous (Unconventional) Oil and Gas Resources in the United States
By U.S. Geological Survey Oil and Gas Assessment Team
Peer Review
Reserve Growth Methodology
USGS Reports
New U.S. Geological Survey Method for the Assessment of Reserve Growth
By Reserve Growth Assessment Team
Reserve Growth of Oil and Gas Fields - Investigations and Applications
By Troy Cook
Peer Review
Below are a list of recent assessment areas. You can also use the National Oil and Gas Assessment Map to browse these assessments.
Eastern Great Basin Oil and Gas Assessments
Uinta-Piceance Basin Oil and Gas Assessments
San Joaquin Basin Oil and Gas Assessments
Sacramento Basin Oil and Gas Assessments
Eastern Oregon-Washington Oil and Gas Assessments
Western Oregon-Washington Oil and Gas Assessments
Williston Basin Oil and Gas Assessments
Permian Basin Oil and Gas Assessments
Alaska Petroleum Systems
Gulf Coast Petroleum Systems Project - Assessments
Appalachian Basin Oil and Gas Assessments
- Overview
USGS Energy Resources Program provides periodic assessments of the oil and natural gas endowment of the United States and the World. This website provides access to new, prioritized, assessment results and supporting data for the United States, as part of the Energy Policy and Conservation Act (EPCA).
Assessment Overview
The USGS assesses potential for undiscovered oil and gas resources in priority geologic provinces in the United States. This website highlights conventional and unconventional (continuous) oil and gas assessments.
Summary of Continuous Assessments
This applications shows maps and tables of all continuous assessments in the United States.
Recent AssessmentsBelow are the latest US Assessments:
National Oil and Gas Assessment Methodology
The U.S. Geological Survey Energy Resources Program assesses the potential for undiscovered oil and gas resources in priority geologic provinces in the United States and around the world (click here for information about World Oil and Gas Assessments). Two methodologies are used by the USGS; one for assessing conventional oil and gas resources and one for assessing unconventional (continuous) oil and gas resources (such as shale gas and coalbed gas). USGS publications detailing and explaining the conventional and continuous assessment methodologies are provided below. These methodologies have been subjected to rigorous peer reviews by non federal panels, and the two panel reports are provided on this page.
Conventional Resources
USGS Reports
U.S. Geological Survey Assessment Concepts for Conventional Petroleum Accumulations
By James W. Schmoker and T.R. KlettU.S. Geological Survey Input-Data Form and Operational Procedure for the Assessment of Conventional Petroleum Accumulations
By T.R. Klett, James W. Schmoker, and Ronald R. CharpentierA Monte Carlo Simulation Method for the Assessment of Undiscovered, Conventional Oil and Gas
By Ronald R. Charpentier and T.R. KlettContinuous Resources
USGS Reports
U.S. Geological Survey Assessment Concepts for Continuous Petroleum Accumulations
By James W. SchmokerU.S. Geological Survey Input-Data Form and Operational Procedure for the Assessment Of Continuous Petroleum Accumulations, 2002
By T.R. Klett and James W. SchmokerAnalytic Resource Assessment Method for Continuous Petroleum Accumulations—The ACCESS Assessment Method
By Robert A. CrovelliFORSPAN Model Users Guide
By T.R. Klett, and Ronald R. Charpentier
Methodology Revisions
Improved USGS methodology for assessing continuous petroleum resources.
Charpentier, R.R., and Cook, T.A.Applying Probabilistic Well-Performance Parameters to Assessments of Shale-Gas Resources
By Ronald R. Charpentier and Troy CookAssembling Probabilistic Performance Parameters of Shale-Gas Wells
By Cook, Troy, and Charpentier, R.R.USGS Methodology for Assessing Continuous Petroleum Resources
By Ronald R. Charpentier and Troy CookNew U.S. Geological Survey Method for the Assessment of Reserve Growth
By Timothy R. Klett, Emil D. Attanasi, Ronald R. Charpentier, Troy A. Cook, Philip A. Freeman, Donald L. Gautier, Phuong A. Le, Robert T. Ryder, Christopher J. Schenk, Marilyn E. Tennyson, and Mahendra K. Verma (Reserve Growth Assessment Team)Variability of Distributions of Well-Scale Estimated Ultimate Recovery for Continuous (Unconventional) Oil and Gas Resources in the United States
By U.S. Geological Survey Oil and Gas Assessment TeamPeer Review
Reserve Growth Methodology
USGS Reports
New U.S. Geological Survey Method for the Assessment of Reserve Growth
By Reserve Growth Assessment TeamReserve Growth of Oil and Gas Fields - Investigations and Applications
By Troy CookPeer Review
- Science
Below are a list of recent assessment areas. You can also use the National Oil and Gas Assessment Map to browse these assessments.
Filter Total Items: 59Eastern Great Basin Oil and Gas Assessments
The U.S. Geological Survey completed the following assessments of undiscovered oil and gas potential of the Eastern Great Basin Province of eastern Nevada, western Utah, southeastern Idaho, and northwestern Arizona 5019.Uinta-Piceance Basin Oil and Gas Assessments
The U.S. Geological Survey (USGS) has conducted a number of geology-based assessments of undiscovered oil and gas resources in the Uinta-Piceance Basin (USGS Province 5020) of western Colorado and Eastern Utah. Recent assessments include.San Joaquin Basin Oil and Gas Assessments
The U.S. Geological Survey completed the following assessments of undiscovered continuous oil and gas resources of the Monterey Formation, San Joaquin Basin Province 5010.Sacramento Basin Oil and Gas Assessments
The U.S. Geological Survey completed the following assessments of undiscovered natural gas resources of the Sacramento Basin Province of California 5008.Eastern Oregon-Washington Oil and Gas Assessments
In 2006, the U.S. Geological Survey (USGS) completed the following assessments of undiscovered gas resources of the Eastern Oregon and Washington Province 5005.Western Oregon-Washington Oil and Gas Assessments
The U.S. Geological Survey completed the following assessments of undiscovered oil and gas resources of the Western Oregon and Washington Province 5004.Williston Basin Oil and Gas Assessments
The U.S. Geological Survey completed the following assessments of conventional and continuous oil and gas resources of the Devonian Three Forks Formation and Devonian and Mississippian Bakken Formation in the Williston Basin Province 5031 of North Dakota, Montana, and South Dakota.Permian Basin Oil and Gas Assessments
The USGS has conducted several assessments of undiscovered oil and gas in formations in the Permian Basin of western Texas. This inlcudes the following.Alaska Petroleum Systems
The Alaska Petroleum Systems project has three main objectives: (A) conduct research that increases our understanding of Alaska petroleum systems, (B) conduct assessments of undiscovered oil and gas resources, and (C) deliver energy-resource information to land and resource managers, policy makers, and the public.Gulf Coast Petroleum Systems Project - Assessments
This site highlights the assessments of the Gulf Coast Petroleum Systems Project. Scientifically robust assessments of undiscovered, technically recoverable hydrocarbon resources are published in a variety of USGS publications. This project also conducts research on the processes that impact the formation, accumulation, occurrence and alteration of hydrocarbon energy resources. The Gulf Coast...Appalachian Basin Oil and Gas Assessments
The USGS has conducted numerous assessments of undiscovered oil and gas in the Appalachian Basin, including studies of the Marcellus Shale. The region extends from Alabama to Maine. The following is an overview of the assessments. - Data
- Publications
- Web Tools
- News
- FAQ
- Partners