The BDM Corporation, under contract to the Department of Energy/Morgantown Energy Technology Center, is collecting geologic and engineering data on Devonian shales from 10 sites in the Appalachian, Michigan and Illinois Basins. As part of that project, three wells were drilled into, collected up to 60 feet of oriented core, and tested the Devonian Rhine street Shale in the Appalachian Basin. Those wells were: L. B. Southwick #1, Crawford County, Pennsylvania; P. D. McCartney #1, Mahoning County, Ohio; and A. B. Wilson #19, Wirt County, West Virginia.
The target areas for drilling the wells was based on data from the past EGSP. Shale thickness, thermal maturity, organic content and stress distribution were factors considered in target selection. Data collected from the wells confirmed the presence of the required factors in the target areas. Petrophysical testing of samples collected from the core indicate the porosity and permeability for the shale is low. The maximum porosity found was 6.8 percent and maximum permeability (at reservoir pressure and for a nonfractured sample) was 7.24 d.
Production testing in the wells yielded mixed results. The L. B. Southwick #1 initially had a production of 3,000 cf/d, but eventually fell off to 800 cf/d. Core samples from the P. D. McCartney #1 had large volumes of gas initially desorbed, but the well yielded no production when tested one week after completion. The A. B. Wilson #1 was able to maintain a flow rate of 8 Mcf/d.
The L. B. Southwick has been stimulated using explosives. Preliminary indications are that it had minimal effect on production. Plans are in progress to foam fracture the P. D. McCartney.
In 1976, the U.S. Department of Energy (DOE) initiated a program designed to expand the knowledge base and understanding of unconventional energy resources. The Eastern Gas Shale Project (EGSP) was to make an assessment of the commercial production potential of natural gas from Middle and Upper Devonian shales in the eastern United States. The specific objectives of the EGSP were:
* Evaluate recoverable reserves of gas in the shales;* Enhance recovery technology for production from shale reservoirs;* Stimulate interest among commercial producers regarding production of gas from Devonian shales.
In October 1984, DOE/Morgantown Energy Technology Center (DOE/METC) awarded a contract to The BDM Corporation for the Installation of a Devonian Shale Reservoir Testing Facility and Acquisition of Reservoir Property Measurements. Geologic and engineering data collected through this project, when coupled with data collected by the past EGSP, will provide a better understanding of the mechanisms and conditions controlling shale gas production.
DOE/METC designated 10 target areas from which data for this project will be collected (Figure 1). Two target areas in the Michigan Basin will test the Antrim Shale while an Illinois target will evaluate the New Albany Shale. In the Appalachian Basin, seven target areas have been identified for testing. Four targets (D, E, F, and J) will test the Rhinestreet Shale and the remaining three (G, H, and 1) will test the deeper Marcellus Shale. The target areas were the selected based on work completed in the EGSP. Criteria used to select these sites included: shale thickness, organic content, mechanical stress distribution and thermal maturity.