The Utica Shale contains about 38 trillion cubic feet (TCF) of undiscovered, technically recoverable natural gas (at the mean estimate) according to the first assessment of this continuous (unconventional) natural gas accumulation by the US Geological Survey (USGS). The Utica Shale has a mean of 940 million barrels of unconventional oil resources and a mean of 208 million barrels of unconventional natural gas liquids.
The Utica Shale lies beneath the Marcellus Shale, and both are part of the Appalachian Basin, which is the longest-producing petroleum province in the United States. The Marcellus Shale, at 84 TCF of natural gas, is the largest unconventional gas basin USGS has assessed. This is followed closely by the Greater Green River Basin in southwestern Wyoming, which has 84 TCF of undiscovered natural gas, of which 82 TCF is continuous (tight gas).
The Utica Shale assessment covered areas in Maryland, New York, Ohio, Pennsylvania, Virginia, and West Virginia.
|Location of the oil and gas assessment units (AU) for the Utica Shale in the Appalachian Basin. Click to enlarge.|
Some shale rock formations, such as the Utica and Marcellus, can be source rocks— formations from which hydrocarbons, such as oil and gas, originate. Conventional oil and gas resources gradually migrate away from the source rock into other formations and traps, whereas continuous resources, such as shale oil and shale gas, remain trapped within the original source rock.
These new estimates are for technically recoverable oil and gas resources, which are those quantities of oil and gas producible using currently available technology and industry practices, regardless of economic or accessibility considerations.
This USGS assessment is an estimate of continuous oil, gas, and natural gas liquid accumulations in the Upper Ordovician Utica Shale of the Appalachian Basin. The estimate of undiscovered oil ranges from 590 million barrels to 1.39 billion barrels (95% to 5% probability, respectively), natural gas ranges from 21 to 61 TCF (95% to 5% probability, respectively), and the estimate of natural gas liquids ranges from 4 to 16 million barrels (95% to 5% probability, respectively).
USGS is the only provider of publicly available estimates of undiscovered technically recoverable oil and gas resources of onshore lands and offshore state waters. The USGS Utica Shale assessment was undertaken as part of a nationwide project assessing domestic petroleum basins using standardized methodology and protocol.
Kirschbaum, M.A., Schenk, C.J., Cook, T.A., Ryder, R.T., Charpentier, R.R., Klett, T.R., Gaswirth, S.B., Tennyson, M.E., and Whidden, K.J. (2012) Assessment of undiscovered oil and gas resources of the Ordovician Utica Shale of the Appalachian Basin Province, 2012. US Geological Survey Fact Sheet 2012–3116