Morrow valley fill sandstone reservoir characterization with 3‐D, 3‐C reflection seismology

Abstract

Three dimensional, multicomponent (3-D, 3-C) reflection seismology is the technology of the future for reservoir characterization. Application of this emerging technology provides quantitative solutions for porosity and permeability determinations within both clastic and carbonate reservoirs which is unattainable from compressional (P) wave data alone. A 3-D, 3-C seismic survey over a clastic valley fill reservoir in the Pennsylvanian Morrow Formation of southeastern Colorado demonstrates the application of this technology. Morrow valley fill sandstone deposits in southeastern Colorado, are prolific oil reservoirs that are not commonly detected with compressional seismic data. A multicomponent 3-D seismic survey acquired over a portion of the Sorrento field, Cheyenne County, Colorado identifies the reservoir sandstone and its spatial variability. Velocity ratio (Vp/Vs), anisotropy, and shear wave amplitude mapping of the three dimensional, multicomponent seismic survey reveal reservoir sandstone distribution and discontinuities, and a local gas cap is characterized by these data. New evidence of tectonic influence on sandstone deposition and reservoir compartmentalization is presented. These results are achieved in a noisy data environment and are verified by subsurface geological and production data. The findings demonstrate the robust nature of 3-D, 3-C seismic technology and its usefulness for reservoir characterization.