4D FWI using towed-streamer data: A case study near Laverda oil field

Time-lapse (4D) seismic surveys are devised to detect subsurface changes resulting from hydrocarbon production and fluid injection. Full-waveform inversion (FWI) of time-lapse seismic data has been reported to provide high-resolution estimates of 4D changes. However, successful applications of 4D FWI on field data have only been seen in a few surveys, either with high repeatability or with vast velocity changes. We propose a new workflow to tackle some challenges in 4D FWI, such as cycle-skipping and amplitude mismatch between modeled synthetic data and recorded field data and water-layer variations between baseline and monitor surveys. We successfully applied this approach to a 4D towed-streamer survey in the Exmouth basin, Western Australia.