弹性各向异性地震波场纵横波分离研究综述OA

The anisotropic characteristics of subsurface media,arising from mineral crystal structures and geological features such as sedimentary layering and directional fractures,cause seismic wave velocities and polarization directions to vary with propagation direction,complicating subsurface imaging and velocity inversion.Although multi-component acquisition has improved imaging in complex structures like gas clouds using converted waves,it also introduces P-and S-wave coupling in anisotropic wavefields,posing challenges for full-waveform inversion(FWI)and reverse-time migration(RTM),which require wavefield separation to avoid crosstalk.However,conventional curl-divergence-based methods fail to achieve clean separation in anisotropic media due to altered polarization directions.This paper reviews the fundamental theory of P-and S-wave separation in anisotropic media based on the Christoffel equation and its wavenumber-eigenvector and phase-polarization angle relationships,and evaluates five major separation methods—low-rank decomposition,equation decoupling,pseudo-Helmholtz,spatial vector,and intelligent separation—by analyzing their advantages,limitations,and computational efficiency,aiming to guide future developments and provide a stronger theoretical foundation for elastic-wave-based FWI and high-precision RTM.