Reservoir Characterization, 3D Modeling and Simulation of the Upper Jurassic Smackover Carbonate Facies at Little Cedar Creek Field, Northeastern Gulf of Mexico
Little Cedar Creek Field is a mature oil field located in the northeastern Gulf of Mexico. As of March 2011, 12.7 MMSTB of oil and 12,430.6 MMSCF of gas have been produced from the field area. The reservoirs are carbonate facies of the Upper Jurassic Smackover Formation that overlie conglomerate and sandstone facies of the Norphlet Formation and underlie the argillaceous, anhydritic carbonaceous facies of the Haynesville Formation. These carbonate reservoirs are composed of grainstone and boundstone, and the petroleum trap is stratigraphic being controlled primarily by changes in depositional facies. Argillaceous beds of the Haynesville Formation serve as the top seal rock. The producing facies are microbial boundstone characterized by vuggy porosity and nearshore/shoal grainstone characterized by moldic porosity. To maximize recovery and investment in the field, an integrated geoscientific-engineering reservoir-wide development plan is needed, including reservoir characterization, modeling, and simulation. This requires the construction of a 3D geocellular model based on the integration of data from wireline logs, 2D seismic lines, core and thin section studies, and petrophysical analysis. Multiple approaches for modeling the porosity and permeability in the reservoirs are used to improve the model, including conventional geostatisitcal distribution of porosity and permeability values derived from wireline logs, the use of MICP data to determine the pore network parameters, and the modeling of petrophysical rock types. The developed static model serves as the foundation for preforming dynamic simulation. Through dynamic simulation, reservoir performance studies, material balance evaluation, PVT analysis, and Monte Carlo simulation, the reservoir drive mechanism, original oil-in place along with its uncertainty, possible and probable reserves, and undrained portions of reservoirs are determined. The integration of the PVT and reservoir pressure data assists in the assessment of the heterogeneity of the reservoirs and the identification of uncontacted compartments. Based on the location of these compartments in the reservoirs and the dynamic simulation model, the optimum field/reservoir development plan is designed for maximizing recovery from the field.
AAPG Search and Discovery Article #90142 © 2012 AAPG Annual Convention and Exhibition, April 22-25, 2012, Long Beach, California