Seismic Imaging Improvement Thanks to a True Wide-azimuth Pre-processing Sequence Applied to a 3D OBC Dataset

High density wide-azimuth Ocean Bottom Cable acquisitions have proven their efficiency to better image complex structures in the North Sea. Yet conventional pre-processing sequences have not taken into account the full potential offered by such acquisitions (Soudani et al. 2006). In this paper, we demonstrate the advantages of a true wide-azimuthal pre-processing regarding noise attenuation on data where the low signal to noise ratio is a main challenge. Following Soudani et al. (2006), a decomposition of the common receiver gathers into the 3D -px-py domain is used to filter out linear noise. A specific two-step sequence is proposed to attenuate the artefacts produced by the strongly aliased direct wave with acceptable run-time effort and data storage. Our results are compared, before and after pre-stack depth migration, with those derived from a more conventional processing approach.