Knowledge of changes in reservoir properties resulting from extracting hydrocarbons or
injecting fluid is critical to future production planning. Full-waveform inversion (FWI) of time-
lapse seismic data provides a quantitative approach to characterize the changes by taking
the difference of the inverted baseline and monitor models. The baseline and monitor data
sets can be inverted either independently or jointly. Time-lapse seismic data collected by
ocean-bottom cables (OBCs) in the Valhall field in the North Sea are suitable for such time …