Updated Resource Assessment of Undiscovered, Technically Recoverable Shale Gas and Shale Oil Within the Mississippian Barnett Shale, North-Central Texas, 2015

Abstract

The Mississippian Barnett Shale of the Fort Worth Basin (north-central Texas) has been one of the most prolific, self-sourced, onshore shale-gas producing formations in the U.S. since exploitation of the unit began in 1981. Recent estimates of recoverable continuous gas resources in the Barnett Shale are in the range of 43 to 44 trillion cubic feet of gas (TCFG) according to the U.S. Energy Information Administration (EIA) and the Texas Bureau of Economic Geology (BEG), respectively. The U.S. Geological Survey (USGS) last assessed the Barnett Shale within the Bend Arch-Fort Worth Basin Province in 2003 and estimated a mean volume of 26.2 TCFG, with approximately 1.0 billion barrels of natural gas liquids. This assessment included two defined assessment units (AUs) within the Barnett Shale: 1) the Greater Newark East Frac-Barrier Continuous Barnett Shale Gas AU, and 2) the Extended Continuous Barnett Shale Gas AU. An additional AU covering the western portion of the Barnett Shale extent was deemed hypothetical and not quantitatively assessed. These AU areas were based on the presence of one or more limestone units considered to be fracture barriers, which included the underlying Viola-Simpson limestones and overlying Marble Falls limestone. This assessment, however, only included data from vertical drilling development. Since 2003, horizontal drilling technology has dominated subsequent exploration of the reservoir, with more than 16,000 horizontal wells currently drilled into the Barnett Shale. As successful drilling and production within the Barnett has expanded beyond the previously defined assessment unit boundaries, the newly revised USGS assessment incorporates new data, focuses on thermal maturity boundaries, and utilizes geochemical parameters, such as the hydrogen index (HI). In addition, the newest assessment incorporates both gas and oil potential into the revised estimates for undiscovered, technically recoverable petroleum hydrocarbon resources, particularly in the liquids-rich northeastern region of the Barnett Shale, where both gas and oil drilling occur.

AAPG Datapages/Search and Discovery Article #90259 ©2016 AAPG Annual Convention and Exhibition, Calgary, Alberta, Canada, June 19-22, 2016