Hambert-Aristocrat Field, DJ Basin, Colorado, USA
The Case Study presented here was conducted as part of a larger interdisciplinary study of reservoir compartments and heterogeneity in the Hambert-Aristocrat field, Denver Basin of Colorado, funded to the Colorado School of Mines Petroleum Engineering Department by the U.S. Department of Energy under Contract No. DE_AC22-93BC14891. A report on the entire study can be obtained from the Office of Natural Gas and Petroleum Technology, U.S. Department of Energy, Washington, DC 20585.
Only the geologic reservoir characterization portion of this study is presented here. Geologic reservoir characterization---utilizing geologic, geophysical, and engineering data in an integrated and optimal fashion--- provides the cornerstone of any improved recovery and reservoir management strategy. In this case, approximately 1100 wells, several cores, well production and completion information, and a partial 3D seismic survey were utilized to develop a comprehensive geological reservoir model. Analysis of such a large set of information required a data management system. We developed a system utilizing the PC because it is the choice of computing environments by many Independent Operators. Results of the study revealed much more diversity and complexity in reservoir characteristics than had previously been recognized. It is these results that are presented below.
It is worth noting the main conclusions of the full interdisciplinary project. Improved understanding of the geology of the field area---coupled with petrophysics, estimating parameters of net pay, drainage area, and recovery factor, then reservoir simulation history matching---led to an increase in the reserve estimates over earlier estimates. For a detailed 12+ Section focus area, the revision in reserve estimates has an estimated incremental net present value (discounted at 10%) of $14 million. A major conclusion of the project was that interaction of people with different disciplines and integration of diverse data types both led to improved reservoir characterization and reduced uncertainty in the reserve estimates, with significant economic benefit (VanKirk, 1996).