Study of Seismic Data Processing Techniques in Deepwater Slope

Seismic data processing in deep-water slope belt area has always been a challenge for marine seismic data processing. Steep slopes could induce strong diffraction multiples, difficult velocity modelling, weaker illumination. This paper will introduce three key methods on dual direction acquisition seismic data imaging for slope belt area. The first key method is joint multiple attenuation, this method uses 3D SRME,vertex drift high-precision radon multiple attenuation, super CDP gather median filter to multiple attenuation; The second key method is geological constrained velocity modeling. This method uses geological information to restrict the initial velocity which could reduce the impact of rapid land surface change on velocity modeling; The third method is dual direction data merge. After PSDM, this method uses fast and slow wave velocity correction and advantage data to get a dual direction merging data stack section. Joint multiple attenuation could eliminate diffraction multiples effectively, and it can improve the signal to noise ratio which will be benefit for the velocity analysis and final imaging; Constrained velocity modeling could improve the velocity model accuracy in the steep slope area, which can help final imaging to avoid imaging distortion under steep seabed; To get a dual direction merging data stack section is a relabel way to increase data folds and illumination and improve the quality of imaging faults. The successful application of these three methods shows that dual direction acquisition data processing provides an effective way to solve the imaging difficulties in steep slopes in deep water.