Application of 4D Full Waveform Inversion on Ocean Bottom Node Dataset

This technical report discusses the application of 4D full waveform inversion (FWI) on an Ultra High Density Ocean Bottom Node dataset, which involved over 25,000 nodes. The report outlines various methods of 4D FWI, comparing results from a test swath with full production data. It emphasizes the challenges faced when limited data is used, which can lead to sub-optimal results. The study reviews initial tests on two UHDOBN datasets acquired in 2017 and 2023, detailing the methodologies employed, including Parallel and Joint 4D FWI approaches. The findings indicate that using the full dataset significantly reduces overburden leakage and improves imaging quality. The report concludes that both approaches to 4D FWI are robust, with the joint method yielding better results in terms of data quality and iteration reduction. The results correlate well with conventionally processed data, indicating the effectiveness of the applied techniques in subsurface imaging.