The construction of 3D velocity models for prestack depth migration is still a challenging problem in areas of complex structures like e.g. those related to salt tectonics. We use prestack traveltime tomography with dedicated techniques for traveltime interpretation and with adequate methodological choices to solve this problem for a data set characterized by a highly complex salt body. The prestack depth migration result obtained with the determined velocity model confirms the good quality of the obtained model.
Prestack traveltime tomography is a well known technique for velocity model building. However, its use in complex geological settings is not trivial. In fact, adequate choices have to made for its implementation, in particular for the subsurface model parameterization. Moreover, dedicated techniques for traveltime interpretation have to be used since direct interpretation in prestack gathers can be difficult.
