Assessments of Undiscovered Continuous Natural Gas Resources in the Appalachian and Mesozoic Basins, Eastern U.S.A.
Bob Milici¹, James L. Coleman, and Mark A. Kirschbaum
The U.S. Geological Survey (USGS) has recently assessed the technically recoverable, undiscovered hydrocarbon resources of three continuous (unconventional) hydrocarbon accumulations in the eastern United States: the Devonian Marcellus Shale (Coleman and others, 2011), the East Coast Mesozoic basins (Milici and others, 2012), and the Ordovician Utica Shale (Kirschbaum and others, 2012). Because of the development of directional drilling and hydraulic fracturing technology, the volumes of natural gas calculated in the more recent assessments of the Marcellus Shale and Mesozoic basins are significantly greater than those assessed previously by the USGS for these plays. The mean assessment value for Marcellus Shale gas in the Appalachian basin was 1,925 BCFG in 2002 vs. 84,198 BCFG for the Marcellus Shale in 2011. Similarly, the East Coast Mesozoic basins were assessed as containing 348 BCFG in 1995 vs. 3,860 BCFG in 2011. Although four continuous assessment units sourced by the Utica Shale were defined within the Utica-Lower Paleozoic Total Petroleum System in the 2002 assessment of the Appalachian Basin (Milici and others, 2003), the Utica Shale source rock was not quantitatively assessed as a self-sourced continuous reservoir at that time. However, the recent USGS assessment (Kirschbaum and others 2012) of 38,212 BCFG for the Utica Shale was largely in response to the data obtained from more recent development of the Utica Shale play by industry.
AAPG Search and Discovery Article #90207 © AAPG Geoscience Technology Workshop, Unconventionals Update, November 4-5, 2014, Austin, Texas