Wave field separation based on 3D equivalent elastic wave equation in wave number domain

The mixed wave field including P wave and S wave can be obtained after forward modeling or extrapolating based on the conventional elastic wave equation. The coupling wave field can be separated into pure P wave and S wave via Helmholtz decomposition. But the previous method produces amplitude distortion. To eliminate this phenomenon, a new equivalent elastic wave equation was presented in wave number domain taking advantage of the features that the curl of P wave is zero and divergence of S wave is zero. The neo-equation derives from separating the conventional wave equation into two portions contained curl-free and divergence-free. The numerical results show that the method can simultaneously produce the mixed wave field, pure P wave field and S wave field. The amplitude distortion was removed.