Secondary Natural Gas Recovery: Targeted Technology Applications for Infield Reserve Growth in Deltaifc Sand-Rich Low to Conventional Permeability Reservoirs in the Wilcox Group, Lake Creek Field, Texas
The potential for secondary incremental recovery of natural gas exists in complex fluvial-deltaic reservoirs of the Texas Gulf Coast. Four deltaic parasequences were identified using well logs calibrated to cores in the G sandstone. Engineering evaluations of production performance and pressures are compared with reservoir facies; these evaluations demonstrate the importance of identifying reservoir facies in maximizing recovery of natural gas. A well-log-based model to predict the free-water level and effective gas permeabilities was tested and calibrated using Wilcox gas reservoirs. Key reservoir parameters of porosity, water saturation, permeability, and capillary pressure are related in a single equation. Analysis of natural gas reservoirs from the Wilcox Deltaic sandstones in the Houston Embayment (WX-1) in East Texas indicates that reserve growth potential of approximately 60 percent over the current estimate of ultimate recovery is possible in deltaic sandstone reservoirs in the Lake Creek Unit. Detailed geologic, engineering, and petrophysical evaluation of the G sandstone reservoir in the Lake Creek Unit indicates that the maximum additional incremental gas opportunities exist in the flank region adjacent to the area currently developed in the Lake Creek field. The location, number, and economic feasibility of additional wells required to convert this resource to producible reserves were not evaluated.Bureau of Economic Geolog
