Improving the quality of prestack seismic data with the CO CRS stacking method

Common Reflection Surface (CRS) stacking method has been demonstrated to improve the imaging quality, through the last few years, compared with the conventional ZO stacking techniques such as CMP stack or NMO/DMO process. Its stacking operator is data-derived and macro-velocity independent, so it is particularly efficient and robust in case of seismic data characterized by poor S/N ratio and low coverage. In this case study, a practical strategy using partial Common-Offset (CO) CRS stack is proposed to enhance the quality of sparse low fold seismic data. The multiparameter CO CRS traveltime formula, by which any finite offset section can be obtained, is applied to compute partially stacked CRS supergathers, which have improved signal-to-noise ratio compared with the original data and are regularized by filling the gaps in cases of missing traces. These improved prestack data can be used in many conventional processing steps, e.g., velocity analysis or prestack depth migration instead of the original data.