Multicomponent Seismic Technology Assessment of Fluid-gas Expulsion Geology and Gas-hydrate Systems:Gulf ofMexico

F our-component ocean-bottom-cable (4-COBC) seismic data acquired in deep water across the Gulf of Mexico were used to study near-sea-floor geologic characteristics of fluid-gas expulsion systems. Although these 4-C OBC data were acquired to evaluate oil and gas prospects far below the sea floor, the data have great value for studying near-sea-floor geology. The research results summarized here stress the importance of the converted-shear-wave (P-SV) mode extracted from 4-COBC data. In deep water, the P-SVmode creates an image of nearsea-floor strata that has a spatial resolution an order of magnitude better than the resolution of compressional wave (P-P) data regardless of whether the P-P data are acquired with OBC technology or with conventional towed-cable seismic technology. This increased resolution allows the P-SV mode to define seismic sequences, seismic facies, small-throw faults, and small-scale structures that cannot be detected with P-P seismic data.