ISSN 1608-5078 (Online)
Fracture characterization, modeling and uncertainty analysis of a carbonate reservoir with integration of dynamic data (Middle East)
This field case study shows the benefits of fracture characterization and risk analysis. The uncertainty analysis was performed on production, plateau length and ultimate recovery factor. The field has been under production for more than 48 years, nevertheless it has produced less than 2% of the STOIIP. Historical data measurements on production rates (wopr, gor, wcut, etc) and pressures (static and flowing) have been used to constrain uncertain parameters during historical period and then propagate it into the prediction. Due to the low cumulative production, fracture characterization uncertainties have been incorporated (Discrete Fracture Network) together with reservoir uncertainties and geological uncertainties. Several surface/controllable parameters have been considered in the analysis evaluation on Plateau Length and Recovery Factor. The risk analysis accounts for two main recovery mechanisms: gas injection from the crest for Gas gravity drainage and periphery downdip water injection with natural imbibition. Several scenarios of DFN’s and 43 uncertain reservoir parameters with their probability distribution were considered. Experimental Design and Response Surface Methodology was applied to minimize the number of Reservoir simulation runs of the study. Plackett and Burman Experimental Design was used for the Screening Phase. During the screening phase, it has been revealed that 7 uncertain parameters account for more than 80 % of the total variation of Cumulative Oil Production. A detailed Latin Hypercube has been performed with 3 discrete fracture network, controllable uncertain parameters and the 7 most relevant parameters. This risk analysis identified the best cases of each phase of the development, P10 and P90, and the major uncertainties impacting the field development plan. Mitigation, acquisition, and monitoring plan have been defined accordingly to reduce the major impacting uncertainties.
fracture, modelling, uncertainty analysis, carbonate reservoir
Games F. (2018). Fracture characterization, modeling and uncertainty analysis of a carbonate reservoir with integration of dynamic data (Middle East). Georesursy = Georesources, 20(3), Part 1, pp. 154-157. DOI: https://doi.org/10.18599/grs.2018.3.154-157