Deriving a depth velocity model using time migrated data: case study

We present the application to a real dataset of an accurate workflow for time to depth conversion. It allows taking full advantage of an existing time imaging project for leading a depth imaging project. We present here the various steps involved in the imaging sequence. It is based on a dense volumetric dip and residual move-out picking in the prestack<br>time migrated domain. This kinematic information is then demigrated to compute multi-offset un-migrated attributes called seismic invariants used as input data for a multi-offset tomographic inversion. Finally the resulting depth velocity model is used for prestack depth migration. Our application to the real dataset demonstrates that accurate results can be obtained with an efficient turnaround time.