Abstract：Starting from elastic wave equation in VTI medium and through eigenvalue equation and acoustic wave theory,the paper approximately created dispersion equation of qP-wave in VTI medium and deeply studied high-order one-way generalized-screen propagation operator of qP-wave in VTI medium based on disturbed theory of medium.Dissolving the parameter field in VTI medium into uniform anisotropic velocity field,velocity disturbed field and anisotropic parameter disturbed field,the high-order one-way generalized-screen propagation operator of qP-wave is composed of two parts: free propagation item of wavefield in background medium and anisotropic disturbed item.The computation of background field is implemented in wavenumber domain and non-uniform anisotropic disturbed item (including slowness disturbed and anisotropic parameter disturbed items) is computed in space domain.When violent lateral variation of anisotropic parameters takes place,using high-order screen operator can improve the propagation precision of one-way qP-wave in steep dip.It is shown by pulse response tests of models in uniform anisotropic medium and complex anisotropic medium that the high-order generalized-screen operator of qP-wave can not only meet the needs of precision,but also adapt to any strong lateral velocity variations and anisotropic disturbance,which is suitable for seismic depth migration of qP-wave in VTI medium.
