Poststack seismic attributes are beginning to be routinely utilized in the analysis of 3D seismic data for both reservoir development and exploration targets. In addition to conventional geologic and engineering data, seismic attributes can provide valuable insight into how carbonate reservoirs are fractured. Optimized oil production in one prolific Jurassic carbonate reservoir in Saudi Arabia can be affected by fracturing (Pham and Ali, 2003). Proper reservoir management considers that reservoir fluids move differentially along these natural migration pathways. The detailed and accurate mapping of the distribution and extent of these fractures is important for reservoir management. New types of seismic volumetric attributes and better integration of geophysical, geologic, borehole, and engineering data are being adopted to meet this challenge. Volumetric seismic attributes computed from 3D seismic data are being used to map and interpret small faults and fractures that may affect fluid flow. These fractures can enhance reservoir permeability in tight rocks. They can also provide conduits for diagenetic fluids if connected over long distances. Some Saudi Arabian carbonate reservoirs have experienced dolomitization related to fracture swarms clustered across the field. In this study, production is from a cyclical shelf carbonate that has a gross reservoir thickness of more than 300 ft. The well spacing is approximately 2 km. Due to this relatively large well spacing, interwell heterogeneity in the reservoir is undersampled. 3D seismic data along with their computed volumetric attributes play an important role in providing information between wells.

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