3D Zero-Offset CRS Stack for Narrow-Azimuth Data - Formulation and Examples

The common-reflection-surface (CRS) stack is a macro-model independent seismic reflection imaging method that has proved to accurately detect and characterise meaningful events in the pre-stack data. As any 3D data-driven method, it requires an azimuthal distribution of traces as uniform as possible, in order to properly infer necessary information from the data. Its application to 3D datasets with narrow-azimuth acquisitions requires some simplified assumptions of the underlying theory. We present an approximated formulation and a related processing method that still represents an improvement with respect to conventional techniques currently employed. The advantages of the method when performing stacking velocity analysis are demonstrated on a synthetic example