Post-migration image optimization of multi-azimuth legacy data in Central Santos Basin

Abstract

In complex presalt reservoirs such as the Santos Basin in Brazil, improvements in our techniques for combining and imaging legacy datasets can postpone the need for additional costly seismic acquisitions. In this case study, we show how data from several legacy acquisitions with varying azimuths were carefully combined to create a contiguous multi-azimuth image. Two different migration algorithms are used with each having tailored approaches for the weighting and summation of the migrated data. Compared to the legacy image, significant improvement is attained in terms of signal-to-noise ratio, the coherency of evaporite layers, base salt, presalt, and basement events, and the delineation of the pre-salt faults.