Maximizing the value of existing seismic data in the Bahrain Field with wide-azimuth processing technology

Abstract

As seismic processing technology advances, it opens opportunities for further improvements of existing datasets. This is especially important in the case of survey areas that may no longer be accessible for new seismic acquisition. The onshore Bahrain Field is just such a case because massive urban development since the original acquisition of a 3D seismic dataset in 1998-99 precludes any large-scale reshoot effort. The application of new 3D wide-azimuth processing techniques to the Bahrain dataset has substantially improved imaging of both shallow and deep reservoirs. Furthermore, the subset of the data volume that is near-surface/near-offset, and therefore wide-azimuth, has provided better fracture characterization of key shallow oil reservoirs. Here we describe the main processing steps that resulted in these image improvements, and we provide an example of how the azimuthal data improved fracture characterization. tive at that time, which was the deep gas reservoir, but it overlooked the shallower section where most of the oil reservoirs reside. Further, the vertical resolution from the depth migration was relatively low, and the depth-to-time