Kinematic time migration and demigration in a 3D visualization system

Time migration moves reflection events from the point of tangency to the apex of the time migration function while the time demigration moves reflection events from the apex back into the point of tangency. In this paper, we present an attempt to bridge the gap between standard RMS-velocity-based time migration and one using the full 3D depth velocity model. The developed kinematic time migration is based on second-order traveltime approximation in the vicinity of the normal ray using azimuth-dependent NMO velocities, while the kinematic time dernigration is based on second-order traveltime approximation in the vicinity of the image ray using azimuth-dependent migration velocities. Both processes are designed to operate on selected key horizons, which have been identified and picked in a 3D visualization system. This development has been validated with synthetic and real data.