Abstract:A large amount of practices showed that in comparison with ordinary wave equation prestack depth migration approach, the precision of relief surface-based prestack depth migration is higher. In order to further improve the precision and efficiency of prestack depth algorithm, the paper introduced a relief surface-based prestack depth migration algorithm of synthetic shot records, in which the basic idea is to use phase coding method to produce synthetic shot records, realizing prestack depth migration of multiple shot records and improving the computing efficiency; and to use wave equation wavefield continuation to replace elevation static correction of shallow near-surface, improving the precision of migration imaging. The paper gave uniform algorithm and implementing steps of relief surface-based prestack depth migration of synthetic shot records. The tests of Marmous and mountainous models and processing results of practical seismic data in Sichuan mountainous areas showed the mentioned approach in the paper is characterized by rapid computing speed and higher imaging precision, but remaining a small amount of cross-correlation noise produced by wavefield synthesis on the prestack depth migration sections of synthetic shot records.