Avo analysis by simultaneous P-P and P-S weighted stacking applied to 3C-3D seismic data

Abstract

A method has been developed to simultanesously invert P-P and P-S pre-stack seismic data to extract estimates of compressional and shear impedance values. This method uses separately processed P-P and P-S data volumes, each consisting of a series of migrated limited-offset data volumes. These offset data volumes for the P-P and P-S datasets are then weighted and summed to form two separate data volumes representing fractional compressional and shear impedance estimates. These data volumes can thus be used correlate anomalous compressional and shear impedance values that can be related to lithology and pore fluid content changes. This method is compared to a stand-alone P-wave weighted stacking method using a 3C-3D dataset. Initial results show the inclusion of the P-S data significantly improves both compressional and shear impedance estimates.