WASHINGTON – The U.S. Geological Survey (USGS) has released a new estimate for potential additions to domestic oil and gas reserves from reserve growth in discovered, conventional accumulations in the United States. The USGS estimates that the mean potential undiscovered, conventional reserve additions for the United States total 32 billion barrels (bb) of oil, 291 trillion cubic feet (tcf) of natural gas, and 10 bb of natural gas liquids, constituting about 10 percent of the overall U.S. oil and gas endowment.

“As part of the Obama Administration's all-of-the-above energy strategy, we are taking aggressive steps to safely and responsibly expand domestic energy production,” said Interior Secretary Ken Salazar. “USGS's ongoing work to identify and estimate U.S. energy supplies – and to make that information available to everyone - is fundamental to our efforts to continue to grow America's energy economy.”

The U.S. estimates released today are for technically recoverable oil and gas, and do not include reserve growth estimates for Federal offshore areas. These estimates were made using a new assessment methodology developed by the USGS.

Reserve growth is the increase in estimated volumes of oil and natural gas that can be recovered from discovered (known) fields and reservoirs through time. Most reserve growth results from delineation of new reservoirs, field extensions, or improved recovery techniques, thereby enhancing efficiency, and recalculation of reserves due to changing economic and operating conditions.

"By providing geologically based, domestically consistent estimates of the potential additions of oil and gas from the growth in reserves in known fields, and placing that information in the public domain, we are furnishing a valuable projection on how much and where fossil fuels may be produced in the future," said USGS Director Marcia McNutt. "When combined with our estimates of undiscovered resources, policy makers can obtain a more complete picture of domestic, technically recoverable oil and gas."

These volumes represent an estimate of the potential future growth of current U.S. reserve estimates over time based on current technologies, and greater understanding of current reservoirs, among other advances. For comparison, the current mean USGS estimates for undiscovered, technically recoverable conventional oil and gas resources from onshore and underlying State waters are 27 bb of oil and 388 tcf of natural gas, respectively.

Reserve growth is a component of the overall oil and gas endowment, but is distinct from reserves and from undiscovered, technically recoverable resources – all three important but separate measurements used in efforts by industry and government to make energy decisions based on the best available science.

Unlike past estimates of reserve growth that relied on statistical extrapolations of growth trends, the new USGS assessment is based on detailed analysis of geology and engineering practices used in producing fields. The assessment uses both published and commercial sources of geologic information and field-production data.

Region Mean Barrels of Crude Oil

Mean Cubic Feet of Natural Gas

Mean Barrels of Natural Gas Liquid 1. Alaska/Pacific Region

20bb 32tcf 1bb 2. Colorado Plateau/Basin & Range

2bb 18tcf 1bb 3. West Texas/Eastern New Mexico

4bb 52tcf 3bb 4. Gulf Coast

3bb 144tcf 4bb 5. Midcontinent/Eastern Region

2bb 45tcf 1bb Totals 32bb 291tcf 10bb

Continuous, or unconventional, oil and gas accumulations, such as shale gas, tight gas, and tight oil were removed from the data set for this study. No attempt was made to estimate the economic viability of the recoverable oil and gas as part of these future projections.

“Today's estimates are more good news for U.S. energy security, and affirm the need for the all-of-the above energy strategy that the President has implemented,” said Salazar, noting that U.S. dependence on foreign oil has gone down every year during the Obama Administration, including a reduction in net oil imports by ten percent – or one million barrels a day – in the last year alone. Total oil production from federal lands and waters has increased 13 percent during the first three years of this Administration, compared to the last three years of the previous Administration. Oil production in the first quarter of 2012 was higher than any time in the last 14 years and natural gas production is at its highest level ever.

Estimates of reserve growth for the world, excluding the United States, were released in June 2012 and total 665 bb of oil, 1,429 tcf of natural gas, and 16 bb of natural gas liquids.

USGS is the only provider of publicly available estimates of undiscovered technically recoverable oil and gas resources and reserve growth of the world, exclusive of the Federal offshore. This U.S. assessment was undertaken as part of a project assessing U.S. petroleum basins using standardized methodology and protocol.

To learn more about this or other geologic assessments, please visit the USGS Energy Resources Program website. Stay up to date with USGS energy science by subscribing to our newsletter or by following us on Twitter.

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