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Characterization of fractured carbonate reservoirs aims at delineate and constraint various data entries to help providing realistic model, which ultimately can be used to predict reservoir dynamic behavior in the near- and far future, hence helps field development planning. In the structurally complicated and highly faulted SE Abu Dhabi region, two hydrocarbon Fields (A and B) are currently under development. We aim at characterizing the fracture system in this region by integrating both direct and indirect data sets to avoid possible early water cut by the existing seismic faults and to help increasing the productivity by the existing relatively short fractures associated with these faults.In this paper we extensively used seismic attributes analyses including curvature, discontinuity and semblance to characterize the seismic fault system in SE Abu Dhabi. We also incorporated the available well data including FMI, CMI and geomechanical data such as elastic and mechanical properties and stress profiles to characterize these seismic faults with their associated sub-seismic fractures. Further, we used basic structural assumption of the regional paleo- and current stresses together with the in-situ stresses to help estimating the potential openness of these fractures over geologic time.Results reveal that the SE Abu Dhabi has two regions with different structural settings; an eastern region wherein the two Fields exist, and a central region to the west. The eastern region close to the border with Oman is characterized by relatively high deformation, which has resulted in more intense folding in a highly elevated terrain, and faulted with two prominent conjugate-like fault sets; N75W and N45W. The central region is characterized by low elevated terrain comprising gentle folds and the existence of a prevailing N75W fault and less dominant N45W faults. In both regions these seismic faults are segmented laterally and vertically with the existence of several relay-ramps and small scale flower structures with limited fault throws forming numerous undulations.The significance of these results is that the development planning has been mainly governed by the existing fault patterns in both regions, where seismic faults with their associated fractures control placement, length and direction of the new planned horizontal wells. It is recommended to place the horizontal wells in the NE direction for well stability and production improvement. The horizontal wells in this direction should be placed relatively away from aquifers both vertically and laterally to avoid early water-cut. The presence of the flower structures, which can be valuable exploration targets, may need different well design for development. |
