PP/PS PSDM, AVO and Joint Inversion Applied to a Virgin Exploration Area in the North Sea

Wintershall Norge ASA have identified a Palaeocene seismic amplitude anomaly in blocks 33/5 & 6 in the North Sea. The anomaly is located in a virgin area for Palaeocene exploration and there is no analogous anomaly that has been described or drilled within this or adjacent parts of the North Sea (Hughes et al, 2010). Multi component seismic (OBC) was acquired in the summer of 2009 in order to de-risk the prospect. The combination of converted wave (PS) and compressional wave (PP) data can be used to de-risk a prospect before drilling in order to distinguish between lithology and fluid fill. The OBC data were processed by CGGVeritas in the autumn of 2009. A complex 4 component (4C) processing sequence was implemented and imaged through anisotropic PP- and PS-wave pre-stack depth migrations (PSDM). The resulting PS images are of high quality and we demonstrate successful applications of PS AVO analyses and joint PP/PS inversion.