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SWLGS Luncheon Topics

Updated August 05, 2003

March 2001

Workstation Visualization Techniques that Empower the Geologist
Louis Liro, Veritas Exploration Services, Houston TX

Abstract Summary: 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.

Biographical Sketch: Lou Liro has twenty years experience in exploration and field development. His specialties are reservoir stratigraphy, salt tectonics, and petroleum systems evaluation. Prior to joining Veritas, he worked for a major oil company in geophysical and geologic research as well as international exploration. He has worked deepwater exploration projects in Angola, Gabon, Nigeria, Brazil, Trinidad, and the Gulf of Mexico, and was the reservoir stratigrapher for development projects in Brazil and Myanmar. He has published and presented over fifty professional papers on sequence stratigraphy, salt tectonics, and workstation visualization, and has taught courses in sequence stratigraphy and basin evaluation. Lou earned his M.S. in geology from the University of Chicago.