Quantifying anomalies detected on seismic-generated attributes is critical to evaluate carbonate reservoir heterogeneities prior to planning and designing CO2 enhanced oil recovery operations. In this study, facies-based pre-stack inversion method is applied to a 3D compressional wave seismic survey to characterize the Ordovician Red River U4 dolomitic reservoir. The facies-based inversion technique is able to delineate reservoir and non-reservoir facies and quantify porosity from inverted elastic volumes and the developed rock physics model.
The facies-based inversion is a robust technique that incorporates prior facies knowledge into the inversion process to concurrently invert for elastic and litho-facies volumes. The latter method is independent of traditional low frequency related issues and takes advantage of facies-based depth trends from the rock physics model. In this study, the facies-based inversion technique is able to retrieve accurate facies and porosity values at RRU4 by adding information gained from well logs and core description during the inversion process.
Acknowledgements
The authors would like to acknowledge and thank Denbury Onshore for providing the field dataset to the Reservoir Characterization Project (RCP) at Colorado School of Mines to conduct this study. Thanks to Ikon Science for the special permission to provide Ji-Fi license to RCP consortium. Finally, this work would not have been possible without RCP industry sponsors.
