Abstract：Conventional diffraction integral migration, based on Kirchoff's integral of wave equation, is accomplished by putting scattered signals on the apex of diffraction hyperbola according to weighting coeffidents.This migration method can not make a full migration to result in horizontal deviation; therefore, we have to use image ray tracing for an additional depth migration so as to focus energy on the scatter points.It is practically proved that this method reduces seriously signal-noise ratio of seismic section in the case of big migration aperture, or big limits of integration.On the basis of this diffraction integral migration method, we developed a normal ray-tracing integral migration method, which can achieve full migration of reflection interface after twice ray tracings.Then time-depth conversion is made in vertical direction.The depth section produced in this way has no blank area, which sometimes results frcm image ray-tracing depth migration.The theoretical modeling result shaves that the tracing integral migration method is feasible, has some advantages such as fast operation, high signal-noise ratio, etc. and provides accurate velocity model for wave theory depth migration.
