Why have some estimates of undiscovered technically recoverable oil or gas changed so much from previous estimates?
Petroleum geologists have long known that oil and gas resources were present in “tight” or impermeable formations such as shale. But there was no feasible way to extract that oil and gas, so they were not “technically recoverable” and were not included in USGS assessment results.
Thanks to new technologies, oil and gas can now be extracted from “tight” formations, so they can be counted in assessments of undiscovered technically recoverable resources.
Learn more: USGS Energy Assessments
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Assessment of undiscovered oil and gas resources in the Cretaceous Nanushuk and Torok Formations, Alaska North Slope, and summary of resource potential of the National Petroleum Reserve in Alaska, 2017
The U.S. Geological Survey estimated mean undiscovered, technically recoverable resources of 8.7 billion barrels of oil and 25 trillion cubic feet of natural gas (associated and nonassociated) in conventional accumulations in the Cretaceous Nanushuk and Torok Formations in the National Petroleum Reserve in Alaska, adjacent State and Native lands,...
Houseknecht, David W.; Lease, Richard O.; Schenk, Christopher J.; Mercier, Tracey J.; Rouse, William A.; Botterell, Palma J.; Whidden, Katherine J.; Garrity, Christopher P.; Lewis, Kristen A.; Heller, Samuel J.; Craddock, William H.; Klett, Timothy R.; Le, Phuong A.; Smith, Rebecca A.; Tennyson, Marilyn E.; Gaswirth, Stephanie B.; Woodall, Cheryl A.; Brownfield, Michael E.; Leathers-Miller, Heidi M.; Finn, Thomas M.
U.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...
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.
Schenk, Christopher J.; Charpentier, Ronald R.; Klett, Timothy R.; Gaswirth, Stephanie B.; Pitman, Janet K.; Brownfield, Michael E.; Mercier, Tracey J.; Wandrey, Craig J.; Weaver, Jean N.
U.S. Geological Survey 2011 assessment of undiscovered oil and gas resources of the Cook Inlet region, south-central Alaska
The U.S. Geological Survey (USGS) has completed an assessment of the volumes of undiscovered, technically recoverable oil and gas resources in conventional and continuous accumulations in Cook Inlet. The assessment used a geology-based methodology and results from new scientific research by the USGS and the State of Alaska, Department of Natural...
Stanley, Richard G.; Pierce, Brenda S.; Houseknecht, David W.
Assessment of Undiscovered Technically Recoverable Oil and Gas Resources of the Bakken Formation, Williston Basin, Montana and North Dakota, 2008
The U.S. Geological Survey (USGS) has completed an assessment of the undiscovered oil and associated gas resources of the Upper Devonian to Lower Mississippian Bakken Formation in the U.S. portion of the Williston Basin of Montana and North Dakota and within the Williston Basin Province. The assessment is based on geologic elements of a total...
Pollastro, R.M.; Roberts, L.N.R.; Cook, T.A.; Lewan, M.D.
Undiscovered oil and gas resources of Lower Silurian Qusaiba-Paleozoic total petroleum systems, Arabian Peninsula
The U.S. Geological Survey (USGS) recently completed an assessment of the undiscovered conventional oil and gas potential of 128 of the world’s petroleum provinces (U.S. Geological Survey World Energy Assessment Team, 2000). In each province, the USGS defined Total Petroleum Systems, and Assessment Units in each Total Petroleum System, and then...
Ahlbrandt, Thomas S.; Pollastro, R.M.; Schenk, Christopher J. USGS 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...
Re-Assessing Alaska's Energy Frontier
Less than 80 miles from Prudhoe Bay, home to the giant oil fields that feed the Trans-Alaska Pipeline, lies the site of USGS’ latest oil and gas assessment: the National Petroleum Reserve-Alaska and adjacent areas. Managed by the Bureau of Land Management, the NPR-A covers 22.8 million acres, more than the entire state of South Carolina.
Forecasting the World’s Energy Resources
It is difficult to overstate the importance of energy to the American economy. Managing this vital sector depends on knowing how many energy resources we have, how many we use and need, and how these resources are transported.
USGS Estimates 20 Billion Barrels of Oil in Texas’ Wolfcamp Shale Formation
This is the largest estimate of continuous oil that USGS has ever assessed in the United States.
USGS Estimates 66 Trillion Cubic Feet of Natural Gas in Colorado’s Mancos Shale Formation
This is the second-largest assessment of potential shale & tight gas resources that the USGS has ever conducted.
USGS Estimates 53 Trillion Cubic Feet of Gas Resources in Barnett Shale
The Barnett Shale contains estimated mean volumes of 53 trillion cubic feet of shale natural gas, 172 million barrels of shale oil and 176 million barrels of natural gas liquids, according to an updated assessment by the U.S. Geological Survey. This estimate is for undiscovered, technically recoverable resources.
USGS Estimates 21 Million Barrels of Oil and 27 Billion Cubic Feet of Gas in the Monterey Formation of the San Joaquin Basin, California
The Monterey Formation in the deepest parts of California’s San Joaquin Basin contains an estimated mean volumes of 21 million barrels of oil, 27 billion cubic feet of gas, and 1 million barrels of natural gas liquids, according to the first USGS assessment of continuous (unconventional), technically recoverable resources in the Monterey Formation.
Appalachian Basin Energy Resources — A New Look at an Old Basin
Appalachian coal and petroleum resources are still available in sufficient quantities to contribute significantly to fulfilling the nation’s energy needs, according to a recent study by the U.S. Geological Survey.
USGS Releases Unconventional Gas Estimates for Five East Coast Basins
Using a geology-based assessment method, the U.S. Geological Survey estimated a mean undiscovered natural gas resource of 3.9 trillion cubic feet and a mean undiscovered natural gas liquids resource of 135 million barrels in continuous accumulations within five East Coast Mesozoic basins, according to a new USGS report.
3 to 4.3 Billion Barrels of Technically Recoverable Oil Assessed in North Dakota and Montana’s Bakken Formation—25 Times More Than 1995 Estimate—
North Dakota and Montana have an estimated 3.0 to 4.3 billion barrels of undiscovered, technically recoverable oil in an area known as the Bakken Formation.
Permafrost in the National Petroleum Reserve-Alaska
Permafrost forms a grid-like pattern in the National Petroleum Reserve-Alaska, a 22.8 million acre region managed by the Bureau of Land Management on Alaska's North Slope. USGS has periodically assessed oil and gas resource potential there. These assessments can be found here.
2016 Mancos Assessment Map
A map showing the Mancos Shale and the USGS assessment units within the formation.
Oil Well being Drilled into the Bakken Formation
Oil well being drilled into the Bakken Formation in North Dakota in 2015.
Active oil and gas pad near Canyonlands National Park
Active oil and gas pad on Bureau of Land Management lands near Canyonlands National Park, Utah.
Oil and Gas Resources of the Arctic Alaska Petroleum Province
Arctic Alaska Petroleum Province, showing locations of principal geologic features. AF, Alpine oil field; ANWR, Arctic National Wildlife Refuge; NPRA, National Petroleum Reserve in Alaska; PB, Prudhoe Bay oil field
A map showing the Barnett Shale assessment area in east Texas
A map showing the Barnett Shale assessment area in east Texas
The Western Permian Basin
In West Texas and southwestern New Mexico lies the Permian Basin, one of the most productive oil and gas basins in the United States. USGS has assessed both conventional and continuous oil and gas resources throughout the Permian Basin. These assessments, as well as other USGS energy research for the Permian Basin, can be found
...A map showing the Barnett Shale assessment area in east Texas
A map showing the Barnett Shale assessment area in east Texas