Since fractured reservoirs are essential to production, exploration rationales specific to the Devonian shale unconventional gas resource are characterized by a geologic fracture creating mechanism. One such predicts intense fracturing in the shale wherever proximally associated with the major thrust faults of the Appalachian overthrust belt. Gruy Federal No. 1 Grainger Co. (DOE EGSP-TN9), a U.S. Department of Energy (DOE)-funded rank wildcat located in Grainger County, TN, successfully tested that rationale. The well penetrated the Saltville Thrust Fault (stratigraphic throw: over 10,000 feet) and encountered the Devonian-Mississippian Chattanooga Shale in the lower plate. The shale proved to be 720 feet thick, of which 480 feet or 67% was anomalously radioactive (25 API above shale base line). Two hundred twenty (220) feet of core was recovered from the most highly radioactive (organic rich) intervals and a full suite of wireline logs was run. Widespread and locally intense fracturing in the shale, especially in the organic sections, observed in the core and evidenced by the logs vindicates the exploration rationale. The well will be hydraulically fractured and tested to evaluate production potential.

You can access this article if you purchase or spend a download.