Geobody Detection and Multi-Point Statistical Facies Modeling – An Integrated Seismic Approach for Modeling Deepwater GOM Intra-slope Turbidites

Abstract

Seismic attribute analyses have uncovered stratigraphic features not previously observed at the Genesis 14,000’ reservoir level. Combining seismic attribute analyses (spectral decomposition and envelope) and visualization techniques (volume co-rendering, optical stacking and stratal slicing) has revealed sedimentary architectures (amalgamated slope channels, crevasses splays, and confined mini-basins) that are geologically reasonable and consistent with well log interpretations. Prior to attribute analyses, conventional seismic interpretation techniques resulted in ambiguous depositional and trap interpretations that led to large uncertainties in reservoir delineation and prospect identification. Seismic attribute analyses have detected more subtle variations in amplitude and frequency that are depositional in character and associated with lateral variations in channel system morphologies. Low-amplitude areas previously interpreted as muddy channel fills are now interpreted as interfluves located between major avulsed channel systems.

The improved attribute based geologic interpretation for these channelized slope turbidites has been incorporated into a 3D earth modeling workflow that utilizes the detected geobodies to generate a structural framework (reservoir geometry and architecture). This framework provided the basis for probabilistic modeling where depositional facies were generated by integrating well log data with the derived seismic geobodies as a training image for Multi Point Statistical (MPS) modeling. When combined with a robust seismic attribute analysis, 3D earth modeling techniques can easily incorporate seismically derived geobodies to more accurately define the distribution of facies, populate properties, and improve reservoir characterization and forecasting.

This presentation will discuss the above techniques, and show examples of the results and impact on the Genesis 14,000’ series reservoirs.

AAPG Datapages/Search and Discovery Article #90323 ©2018 AAPG Annual Convention and Exhibition, Salt Lake City, Utah, May 20-23, 2018