Application of 3D CRS-OIS to 3D Real Data Acquired in South China Sea

A 3D common-reflection-surface (CRS) stack method with an output imaging scheme (3D CRS-OIS) has been applied to a real 3D marine data acquired in South China Sea. Differed from traditional 3D CRS stack, a pragmatic approach to search local 3D reflection segment is taken such that only three attributes instead of eight will be enough to characterize the local coherency of reflection events in 3D common-offset (CO) data. Then, a bunch of 3D NMO/DMO response is constructed based on each local 3D reflection segment being searched. A superposition of all 3D NMO/DMO responses defines final 3D zero-offset (ZO) CRS stacked image. The application of 3D CRS-OIS in this real case shows that the 3D CRS-OIS provides not only a superior 3D ZO image, but also a better pre-stack dataset with higher signal/noise (S/N) ratio which can be used for subsequent processing. More importantly, the 3D local coherent events being searched can well match reflection events locally thus a very expensive final optimization required by the conventional 3D CRS stack can be avoided.