f A velocity model building technique for pre-stack depth migration

As exploration in complex geology areas becomes more prevalent, the ability to estimate the migration velocity field in such regions will be one of the key elements in the processing sequence. Due to the presence of lateral velocity variations (actual or structurally induced), depth migration, rather than time migration, has to be used to correctly image events in depth . In this paper we present a well tested procedure which combines an interval velocity estimating technique, Logether with a map migration technique (Hadley,1988), This leads to the generation of a velocity model whose seismic response is consistent with both the pre-stack and post-stack data for a.prospect.