Residual dependent FWI sensitivities based on direct nonlinear inverse scattering
Kristopher A. Innanen
Nonlinear, residual dependent FWI sensitivities are the outgrowth of the observation that certain direct nonlinear procedures, available in special case environments/schemes, such as AVO inversion or 1D/1.5D direct nonlinear inverse scattering imaging and inversion, have no FWI generalization – they cannot be found as special cases of any standard FWI procedure. In order to derive general FWI schemes that reduce in this way, an extension of some kind is required to our ideas of FWI sensitivity. A proposal from 2014, namely that the sensitivities be created by varying not the current model iteration, but the forthcoming iteration, is pursued in this paper to confirm that this approach correctly reduces to an existing 1D normal incidence direct nonlinear imaging and inversion scheme, previously derived from inverse scattering considerations.