Abstract

All phases of the upstream petroleum industry, from wildcat exploration to field development, now benefit from massive amounts of available data. Seismic interpretation, in particular, benefits from 3D seismic data volumes that nearly blanket the entire offshore Gulf of Mexico. Depth migration of seismic data has advanced to the point where the interpreter can literally treat views extracted from a three-dimensional seismic volume as a "digital outcrop."

Armed with these data and well control for calibration, it is now possible to rapidly quantify stratigraphic mapping, seismic facies analysis, and fault definition. By interactively decimating the data through opacity and subvolume detection techniques, individual fairways and prospects can be described and evaluated. Co-rendering amplitude with other seismic attribute volumes allows rapid calibration to well data and identification of attribute combinations that effectively delineate exploration and production parameters, providing effective input to reservoir characterization.

We demonstrate these techniques by displaying workflows and examples from 3D prestack depth-migrated seismic volumes covering nearly 300 OCS blocks in the Walker Ridge lease area. Examples of full volume description of allochthonous shallow salt bodies, structural and stratigraphic interpretation in the vicinity of thinning salt and salt welds, use of supra-salt sediment geometries to unravel complex shallow salt re-mobilization history, the identification and 3D mapping of channelized and fan-form sediment intervals, and the mapping of probable field extent utilizing calibrated seismic attributes will be displayed.