Prestack depth migration based on wave equation using time-shift imaging condition

Key words:  prestack depth migration  time-shift imaging condition  computational efficiency  wave equation

Abstract:

In order to improve the efficiency of prestack depth migration of shot field，time-shift imaging condition was used for prestack depth migration. Based on frequency space finite difference operator for continuation, the time-shift imaging condition was used to get the imaging results of the layers among the larger continuation step. Though another inverse Fourier transform is needed, it has little effect on ihe computational efficiency. The impulse and Marmousi model test results show that the proposed method doubles the computational efficiency with the imaging results equivalent to the results of small step.