FWI Imaging through Basalts

We apply adaptive waveform inversion, reflection waveform inversion and broadband FWI imaging to conventional narrow-azimuth towed-streamer seismic data acquired over a deep-water heterogeneous basaltic section. The resulting high-resolution velocity model reveals the structure and physical properties of the basaltic layers in the sub-surface. Spatial differentiation of the broadband acoustic-impedance model recovered using short-offset 60-Hz FWI applied to the unprocessed field data generates a multiple-free deghosted true-amplitude depth-migrated image of acoustic reflectivity. The image is significantly superior to the existing conventional PSDM generated using conventional processing. Parameter selection and real-time dynamic control of the inversion are automated, driven using measurements on data and model that include local phase differences between predicted and observed data weighted by amplitude envelope.