Parsimonious Inversion of the Gravity Anomaly for Salt-base Delineation
S. Re and L. Masnaghetti
Event name: 79th EAGE Conference and Exhibition 2017
Session: Carbonate and Evaporite Environments, Stratigraphy and More
Publication date: 12 June 2017
Info: Extended abstract, PDF ( 1.06Mb )
Price: € 20
A principal difficulty with the inversion of gravity data is the inherent non-uniqueness that exists in any geophysical method based upon a static potential field: since the gravity field is known only on the surface of the earth, there are infinitely many equivalent density distributions beneath the surface that will reproduce the known field. However a proper manipulation of the recorded gravity anomaly together with an adequate choice of the model representation can turn the inversion of the potential-field data into a valid ally for the basement delineation as witnessed by a large number of publications. Under certain assumptions, the method for the estimation of the depth of the basement can be adapted for salt-base delineation: this approach enables an integrated earth model building workflow that exploits the potential-field data library of the client to complement and, if needed, to disambiguate the seismic image. A synthetic example based on a complex salt province is used to illustrate the modelling and inversion process, together with its outcomes.