Acquisition, classification, and evaluation of engineering and geologic information and characteristics of West Virginia petroleum reservoirs amenable to enhanced oil recovery technology, particularly carbon dioxide injection. Final report

Based on available reservoir information, CO2 displacement seems to be the enhanced oil recovery technique most suitable for most West Virginia oil reservoirs. Seventeen reservoirs have been identified as potential candidates for the CO2 displacement process: three Berea, six Big Injun, five Gordon, one Gordon Stray, one Fifth, and one Squaw--Weir sand reservoir. The total volume of oil remaining in these 17 reservoirs is estimated to be more than one billion barrels. The fields are all within a relatively small geographic area and constitute a significant target for enhanced oil recovery technology. There are, however, many difficulties in working with expensive fluids in old fields containing many abandoned wells. Injectivity of liquid CO2 in West Virginia oil reservoirs has been demonstrated to be higher than that for water or natural gas. In connection with raising pressures prior to CO2 injection, waterflooding has been shown to be effective in two reservoirs previously considered impossible to flood. In the single CO2 displacement process completed in West Virginia, the Granny's Creek project, efficiency of recovery was not high: less than one barrel of additional oil per 20 MSCF of CO2 injected. The injected liquid was found far outside the project area, however, indicating a need for effective confinement. The CO2 process has been demonstrated as effective in displacing oil from a previously waterflooded portion of the reservoir. The three ongoing or projected CO2 projects in the state have many common features, which should simplify the complete analysis when they are completed.