Some problems in velocity analysis for marine deep seismic profiles

The petroleum industry has identified deep seismic profiling as an additional means to assess frontier exploration areas. Those of us working within the British Institutions Reflection Profiling Syndicate (BIRPS) have recognized velocity analysis to be one of the most crucial steps in the data processing stream for deep seismie data. Although also true for conventional processing for sedimentary basins, the drastic differences in the depth, seismic velocity, and structural complexity of the target in the crust and upper mantIe force one to change the relative emphasis placed on the various aspects of velocity analysis.