An Integrated Technical Workflow for Earth Model Building, Deepwater Gulf of Mexico

Advances in geophysical seismic imaging have traditionally been driven primarily by mathematical algorithms and elastic wave theory. While these methods have served the industry well, there are many geographical areas where the subsurface structural complexity is such that geophysics and remote sensing alone are not enough. Nowhere is this truer than in the deep water Gulf of Mexico allochthonous salt canopy province. For instance, of the approximately 130 wells that have been drilled to 27,000 feet or more in the deep water Green Canyon, Walker Ridge, Garden Banks, Keathley Canyon and Alaminos Canyon areas, only a small number have so far proven commercial. From this and other analysis, it is clear that the risk factors for a sub-salt well increase as the quality of sub-salt seismic illumination and confidence of structural positioning decreases. Without a good image, how is it possible to properly define structural integrity, migration pathways, timing, seal and a host of other key components necessary for a successful exploration, appraisal or development well? At WesternGeco we have instituted multi-disciplinary Basin-to-Prospect teams assembled from various Schlumberger segments to apply innovative techniques and technologies to build better integrated earth models for eventual understanding of exploration risk. This study will focus on parts of those integrated methods we have developed to address sub-salt imaging problems including TTI anisotropy, well log analysis, salt geometry considerations and incorporation of non-seismic methods into the earth model building process.

AAPG Search and Discovery Article #90142 © 2012 AAPG Annual Convention and Exhibition, April 22-25, 2012, Long Beach, California