Philadelphia Inquirer
August 23, 2011
U.S. revises amount of Marcellus gas higher, much higher
Andrew Maykuth
The U.S. Geological Survey (USGS) on Tuesday announced a dramatic upward revision of its estimate of recoverable natural gas from the Marcellus Shale. The new figure released Tuesday is 84 trillion cubic feet of “undiscovered, technically recoverable” natural gas, which is 42 times greater than its 2002 estimate of two trillion cubic feet. The USGS also estimates that there are 3.4 billion barrels of “undiscovered, technically recoverable” natural gas fluids. The USGS assessment attributed the increase to new geologic information from shale-drilling operations, which have ramped up in recent years because of new developments in extraction technology. The new survey suggested that the gas reserves are 43 trillion cubic feet to 144 trillion cubic feet, and the gas liquids are 1.6 to 6.2 barrels, with a 95 percent probability of the low range and 5 percent of the high range. The USGS Marcellus assessment covered areas in Kentucky, Maryland, New York, Ohio, Pennsylvania, Tennessee, Virginia and West Virginia. The reference to “technically recoverable” reserves refers to those quantities of oil and gas producible using currently available technology and industry practices, regardless of economic or accessibility considerations.