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United States Assessments of Undiscovered Oil and Gas Resources Active

By Central Energy Resources Science Center April 19, 2019

Explore US Undiscovered Oil and Gas Assessment Provinces

Assessment results, publications, data and more are available

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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

Image shows a map of the assessment units of the 2018 Delaware Basin oil and gas assessment

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

Interactive map and chart highlighting USGS Domestic Continuous (Unconventional) Oil & Gas Assessments, 2000-Present

This applications shows maps and tables of all continuous assessments in the United States.

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Recent Assessments

Below are the latest US Assessments:

Browse 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

American Association of Petroleum Geologists Committee on Resource Evaluation (CORE) Subcommittee to review the United States Onshore Continuous (Unconventional) Gas Assessment Methodology Used by the USGS

 

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

American Association of Petroleum Geologists Committee on Resource Evaluation (CORE) Subcommittee to review the Growth-to-Known Reserves

 

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: 59

Below are datasets related to the National Oil and Gas Assessments.  

Legacy downloadable data
Filter Total Items: 34
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Below are publications associated with this project.

Filter Total Items: 93

Petroleum systems and assessment of undiscovered oil and gas in the Anadarko Basin Province, Colorado, Kansas, Oklahoma, and Texas: USGS Province 58

This publication provides research results and related data in support of the U.S. Geological Survey assessment of the undiscovered oil and gas resource potential of the Anadarko Basin Province of western Oklahoma and Kansas, northern Texas, and southeastern Colorado. This province area includes the Las Animas arch of southeastern Colorado, part of the Palo Duro Basin of Texas, and the Anadarko Ba
By
Energy Resources Program, Central Energy Resources Science Center, Geosciences and Environmental Change Science Center

Map of assessed coalbed-gas resources in the United States, 2014

This report presents a digital map of coalbed-gas resource assessments in the United States as part of the U.S. Geological Survey’s (USGS) National Assessment of Oil and Gas Project. Using a geology-based assessment methodology, the USGS quantitatively estimated potential volumes of undiscovered, technically recoverable natural gas resources within coalbed-gas assessment units (AUs). This is the t
By
Energy Resources Program, Central Energy Resources Science Center

Map of assessed tight-gas resources in the United States

This report presents a digital map of tight-gas resource assessments in the United States as part of the U.S. Geological Survey’s (USGS) National Assessment of Oil and Gas Project. Using a geology-based assessment methodology, the USGS quantitatively estimated potential volumes of undiscovered, technically recoverable natural gas resources within tight-gas assessment units (AUs). This is the secon
By
Energy Resources Program, Central Energy Resources Science Center

U.S. Geological Survey 2013 assessment of undiscovered resources in the Bakken and Three Forks Formations of the U.S. Williston Basin Province

The Upper Devonian Three Forks and Upper Devonian to Lower Mississippian Bakken Formations comprise a major United States continuous oil resource. Current exploitation of oil is from horizontal drilling and hydraulic fracturing of the Middle Member of the Bakken and upper Three Forks, with ongoing exploration of the lower Three Forks, and the Upper, Lower, and Pronghorn Members of the Bakken Forma
By
Energy Resources Program, Central Energy Resources Science Center

Assessment of continuous oil and gas reservoirs, Paradox Basin, Utah, Colorado, New Mexico, and Arizona

No abstract available
By
Energy Resources Program, Central Energy Resources Science Center

Lower Cody Shale (Niobrara equivalent) in the Bighorn Basin, Wyoming and Montana: thickness, distribution, and source rock potential

The lower shaly member of the Cody Shale in the Bighorn Basin, Wyoming and Montana is Coniacian to Santonian in age and is equivalent to the upper part of the Carlile Shale and basal part of the Niobrara Formation in the Powder River Basin to the east. The lower Cody ranges in thickness from 700 to 1,200 feet and underlies much of the central part of the basin. It is composed of gray to black shal
By
Energy Resources Program, Central Energy Resources Science Center

National Assessment of Oil and Gas Project: geologic assessment of undiscovered gas hydrate resources on the North Slope, Alaska

Scientists with the U.S. Geological Survey have completed the first assessment of the undiscovered, technically recoverable gas hydrate resources beneath the North Slope of Alaska. This assessment indicates the existence of technically recoverable gas hydrate resources—that is, resources that can be discovered, developed, and produced using current technology. The approach used in this assessment
By
Energy Resources Program, Central Energy Resources Science Center

Geologic assessment of undiscovered oil and gas resources: Oligocene Frio and Anahuac Formations, United States Gulf of Mexico coastal plain and State waters

The Oligocene Frio and Anahuac Formations were assessed as part of the 2007 U.S. Geological Survey (USGS) assessment of Tertiary strata of the U.S. Gulf of Mexico Basin onshore and State waters. The Frio Formation, which consists of sand-rich fluvio-deltaic systems, has been one of the largest hydrocarbon producers from the Paleogene in the Gulf of Mexico. The Anahuac Formation, an extensive trans
By
Energy Resources Program, Geology, Energy & Minerals Science Center

Upper Devonian–Mississippian stratigraphic framework of the Arkoma Basin and distribution of potential source-rock facies in the Woodford–Chattanooga and Fayetteville–Caney shale-gas systems

Wireline logs were used to document the stratigraphic framework of Upper Devonian–Mississippian strata in the Arkoma Basin, and maps of high-gamma ray (HGR) log response were used to analyze the spatial distribution of potential source rocks in the Woodford–Chattanooga and Fayetteville–Caney shale-gas systems. The Woodford–Chattanooga shale is a transgressive deposit that accumulated on an arid co
By
Energy Resources Program, Geology, Energy & Minerals Science Center

4D petroleum system model of the Mississippian System in the Anadarko Basin Province, Oklahoma, Kansas, Texas, and Colorado, U.S.A.

The Upper Devonian and Lower Mississippian Woodford Shale is an important petroleum source rock for Mississippian reservoirs in the Anadarko Basin Province of Oklahoma, Kansas, Texas, and Colorado, based on results from a 4D petroleum system model of the basin. The Woodford Shale underlies Mississippian strata over most of the Anadarko Basin portions of Oklahoma and northeastern Texas. The Kansas
By
Energy Resources Program, Central Energy Resources Science Center

Assessment of undiscovered technically recoverable oil and gas resources of Puerto Rico and the Puerto Rico-U.S. Virgin Islands Exclusive Economic Zone, 2013

Using a geology-based assessment methodology, the U.S. Geological Survey estimated means of 19 million barrels of undiscovered, technically recoverable oil and 244 billion cubic feet of undiscovered natural gas in the Puerto Rico–U.S. Virgin Islands Exclusive Economic Zone.
By
Energy Resources Program, Central Energy Resources Science Center

Petroleum system analysis of the Hunton Group in West Edmond field, Oklahoma

West Edmond field, located in central Oklahoma, is one of the largest oil accumulations in the Silurian–Devonian Hunton Group in this part of the Anadarko Basin. Production from all stratigraphic units in the field exceeds 170 million barrels of oil (MMBO) and 400 billion cubic feet of gas (BCFG), of which approximately 60 MMBO and 100 BCFG have been produced from the Hunton Group. Oil and gas are
By
Energy Resources Program

Below are datasets related to the National Oil and Gas Assessments.  

Below are news stories associated with this project.

Below are FAQ associated with this project.

Below are partners associated with this project.

Bureau of Land Management (BLM)

Bureau of Ocean Energy Management (BOEM)

U.S. Department of Energy (DOE)