Improved Deep Target Reservoir Imaging with Broadband WATS Data in the East China Sea

A broadband Wide-Azimuth Towed-Streamer (WATS) survey was acquired in a shallow water region of offshore China for the purpose of resolving strike direction narrow-azimuth acquisition shortcomings. However, the current WATS acquisition is much sparser than WATS surveys in deep water environments. The challenges of sparse acquisition, shallow water, and deep targets, require optimal utilization of the side-gun data as the key to final imaging improvements. This paper presents a comprehensive flow for resolving the imaging challenges of de-ghosting and de-multiple for sparse and shallow wide-azimuth data. Side-gun data clearly enhances the final target reservoir imaging and better ties the well. Contribution analysis further provides valuable guidance for future acquisition designs in similar geographical and geological conditions. It is recommended that the 2nd pass source-boat should be nearer to the streamer vessel in order to obtain better azimuth distribution.