oa Enhanced seismic interpretation using multiple seismic volumes over an offshore field, Abu Dhabi, United Arab Emirates

New seismic data reprocessing has improved seismic interpretations for a major Middle East offshore oil field. Significant new fault patterns have been identified within a Kharaib carbonate reservoir using multiple seismic volumes. These were generated from post-stack reprocessing of a full-field 1,500 square km data volume and full reprocessing from field tape of a crestal 200 square km data set. The new fault framework will be incorporated into geologic models for simulation modeling that will help drive the development plan for the field. The full-field post-stack reprocessing flow was designed to reduce noise, thereby enhancing stratigraphic detail and fault definition. Near-, mid-, far-, and full-stacks, spectral whitening and spectral decomposed data show different<br>degrees of resolution. The full reprocessing from field tape used a processing flow that was specifically designed to address severe water-bottom energy surface noise and variable short-period reverberatory multiples. It used separate processing flows for hydrophone and geophone data. Noise reduction from the reprocessing allowed consistent and efficient automated horizon picking. The interpretation approach included the generation of new horizons and a disciplined approach to fault identification using multiple volumes and attributes. From the new data, automated horizons were picked, which led to better identification of small faults using horizon-based attributes. The new data allowed us to identify pervasive NE-SW and N-S faults in parts of the field and to subdivide major faults into smaller faults at different stratigraphic levels. These encouraging results motivated us to plan full-field full reprocessing from field tape.