Full Waveform Inversion via Matched Source Extension

Abstract

Summary Matched Source Waveform Inversion introduces additional degrees of freedom into waveform modeling in the form of trace-dependent source modification, allowing close data fit at all stages of the inversion process. Penalizing source modification leads to an optimization problem with the same global minimum as Full Waveform Inversion, but with less tendency to develop local minima caused by cycle-skipping. We implement and analyze a simple variant of this technique, using constant density acoustics and a transmission configuration, and explain the very close relation of this method to traveltime tomography for mildly heterogeneous velocity models. In common with other data domain waveform tomography methods, the Matched Source objective function may develop multiple local minima, despite avoiding cycle-skip in data residual, if multiple ray paths connect sources and receivers.