Integration of Rock Physics and Seismic Interpretation – An Overlooked West African Stratigraphic Hydrocarbon Play

Summary Hydrocarbon identification within class 1 AVO reservoirs has tended to be problematic using conventional petroacoustic analyses due to the dominance of the hard rock matrix, leaving poor differentiation of fluids from elastic parameters. Additionally, good quality long offset seismic data is a pre-requisite for any attempt at fluid and lithology discrimination. The challenge required in this study is to de-risk a previously overlooked stratigraphic play, dominated by class 1 AVO behavior, constrained by limited offset seismic, but embellished by a recent well with high quality comprehensive wireline logs. Integration of petroacoustic modeling with conventional interpretation, frequency and amplitude seismic attributes, and seismic co-rendering has revealed an extensive new stratigraphic play offshore Cameroon. Rock physics results from the recent well IM-5 have been compared with other drilled reservoirs in the region to calibrate different seismic attribute responses across the newly defined Intra Isongo reservoir fairway. This has led to development of a qualitative predictive model with respect to thickness, porosity, and net to gross. Recognition and delineation of the play is presented here with a set of geophysical guidelines to aid exploration in similar petroacoustic provenances.