Velocity modelling and prestack depth imaging below complex salt structures: a case history from on-shore Germany

In recent years, the advances in velocity model building and depth imaging have provided a better understanding of complex subsalt plays. The tomographic approach to subsurface velocity modelling, using interpretive processes, has led to significant progress in solving subsalt imaging problems, which were once considered to be impenetrable barriers. We show how gravity data, as an alternative data source, can be integrated into iterative velocity-depth model building to constrain the overburden velocity model and delineate the shape of the salt body above the target reflector. In this way, a structurally accurate image of subsalt reflectors is achieved.