Poroelastic reverse time migration based on the true-amplitude vector wavefield decomposition

Abstract In the field of exploration seismology, reverse time migration (RTM) stands out as a premier imaging technique due to its ability to accurately depict subsurface structures by solving the complete two-way wave equation. However, most existing RTM algorithms are primarily designed for acoustic or elastic media, which limits their effectiveness when dealing with the complexities of poroelastic medium. To address this limitation and enhance imaging accuracy, we propose a novel vector wavefield decomposition method specifically tailored for poroelastic medium. This method enables the production of vector fast P-wave, slow P-wave as well as S-wave with correct phases and amplitudes. By utilizing the decoupled fast and slow P-waves, we propose a comprehensive poroelastic RTM workflow that facilitates high-resolution imaging of subsurface structures with varying porosities. Our method not only mitigates crosstalk artifacts during imaging but also provides a more accurate representation of the subsurface by considering the unique characteristics of poroelastic media. Through numerical experiments, we demonstrate the distinct imaging capabilities of our proposed method for both velocity and porosity variations. The results highlight the potential of our approach to significantly improve the imaging of complex subsurface structures in poroelastic environments, offering valuable insights for hydrocarbon exploration and reservoir characterization.