C-Wave Imaging – Kirchhoff PSTM versus DMO

Recently pre-stack depth migration has been extended to handle converted wave data and new methodologies for performing C-wave focusing analysis have been proposed and successfully tested (Audebert et al, 2001). Unfortunately, the layer-by-layer model building inherent to the PSDM sequence is still a delicate and time consuming task. That is why the PSTM route, with its more robust approach to velocity picking, remains very appealing, despite its simpler assumptions. Kirchhoff PSTM is routinely applied on huge 3D data sets for compressional waves. Such an algorithm has also been developed to handle converted waves. This requires dealing with, either both Vp and Vs velocity fields or with