Application of a 3D orthorhombic FWI to a field data set from the North Sea

Abstract

"The application of a full-wave form inversion (FWI) to field data offers many challenges especially when the anisotropy footprint on the data is large and must be handled by our modeling and inversion methodology. However, by acknowledging the anisotropic nature of the medium, we share a successful application of an acoustic orthorhombic FWI to a 3D field data set from the North sea. We properly parameterize the acoustic orthorhombic model with one velocity and five dimensionless anisotropy parameters. Based on previous parameter resolution studies and given the quality of the data, we focus on inverting 4 parameters only (out of the 6 describing an acoustic orthorhombic model). An amplitude independent objective function helps us mitigate the amplitude fitting issue due to the acoustic approximation. Moreover, model regularization and constraints help push the model parameters toward high resolution and geologically consistent structures. The inverted model shows good agreement with well-log information, especially at the reservoir location."