Unlocking New Reservoir Insights with FWI

Full Waveform Inversion (FWI) has become a standard method for generating high-resolution subsurface velocity models. Advances in FWI now allow the use of the full recorded wavefield, including diving waves, primary reflections, and multiples, leading to improved velocity updates even below the maximum penetration depth of diving waves. These detailed velocity models enhance seismic imaging and provide valuable input for Quantitative Interpretation (QI), which is essential for reservoir characterisation. We present here two case studies that illustrate the benefits of FWI for QI purposes. The first study, offshore Norway, applies elastic FWI to handle strong velocity contrasts beneath thick chalk layers, demonstrating how high-resolution velocity and seismic images improve fault detection and stratigraphic amplitude-versus-angle (AVA) inversion. The second case study, onshore Oman, showcases recent advances in land FWI and FWI Imaging, leading to sharper fault imaging and better stratigraphic AVA inversion when combining high-frequency velocity models with improved seismic images. These two case studies highlight the importance of retrieving velocity models within the same frequency bandwidth as the seismic images to accurately capture thin geological features. They also demonstrate the added value of using FWI-derived velocity models to enhance subsequent stratigraphic AVA inversion.