A new parameterization for anisotropy update in full waveform inversion

Abstract

Full Waveform Inversion (FWI) is now used regularly by the industry to update velocity models. These algorithms often take into account anisotropy but do not update it. We introduce a set of parameters, new in the scope of FWI, which have better orthogonal properties in comparison to other equivalent sets. This was done in an attempt to mitigate the existing ambiguity when jointly estimating anisotropy and velocity from FWI. After demonstrating the properties of this new parameter set, a practical application to a North Sea field dataset is then presented. Our FWI result reveals interesting velocity and anisotropy details associated with features in the near surface geology; an associated improvement in the seismic image is also observed.