Algorithmic Approaches to Psdm for Imaging Beneath Salt Structures - An Example from the Uk Sns

Areas of structural complexity that include strong lateral velocity contrasts prove considerable obstacles for imaging and are best addressed by pre-stack depth migration (PSDM) . However, the ability of PSDM schemes to tackle such problems is varied and much depends on the approach to initial velocity model building. An excellent testing area for PSDM is provided by a steep (and/or fault) sided salt diapir piercing its overburden. We outline the fundamental differences between two PSDM schemes from separate contractors and present their success on imaging a 2D data set over a prospect underlying salt in Southern North Sea Block 48/3b.