Limits on the velocity model

In order to obtain from seismic data a good image of complex geologic structures we must meet several demands. First among these is a correct velocity model whose detail is related to the complexity of the structures and which is geologically plausible. In order to limit our search for the velocity model to part of the model space we should incorporate in our model construction a priori geophysical and geological constraints on the model. My presentation deals with these limits on the velocity model.