Geologic Constraints on Seismic Inversion

Velocity model estimation from seismic data using prestack depth migration is an un-derdetermined problem: there are many subtly diierent models which are not kinematically equivalent. As these models can give rise to dramatically diierent interpretations and decisions there is a clear need for a selection criterion in order to choose the "best" (i.e. geologically most plausible) one. Interpreter guided velocity estimation provides this criterion but is non reproducible and non quantiiable while automatic methods (which are both reproducible and quantiiable) will nd just one out of many kinematically equivalent models and mostly one which is geologically not attractive. Application of geologic constraints in conjunction with inversion by Diierential Semblance Optimization produces models that are both geologically appealing, kinematically correct and have a very good t to observed data.