| As the most physical of the shot-profile wave equation pre-stack depth migration involving huge extrapolation calculation, the calculation is extremely time-consuming and less efficient. When the acquisition carried out in the complex surface observation, this flaw is more obvious.Plane wave has the overall direction, compared with the normal migration, the plane-wave imaging results can be comparable to, and has a high computational efficiency. Synthesis of plane waves are implicit assumption that the level of the surface, so the surface in complex conditions, can no longer conducted in accordance with conventional synthesis. Has been adopted for the wave equation pre-stack depth imaging methodology based on complex surface, the paper extends the plane wave migration to adapt the complex surface, this method has the well results and the same high efficiency.The first part of this paper introduces the method of wave equation pre-stack depth migration in complex surface, the second part introduces the details of the plane-wave migration theory,the development and the test results, the third part describes two methods of plane-wave migration under the complex conditions, the fourth part of the pre-stack depth imaging conditions were discussed with the smoothing approach.The results show that the use of the same methodology of wave equation pre-stack depth imaging based on complex surface, could be extend plane wave migration to complex conditions, this method has the same good results and high efficiency. The one-step realization of direct synthesis of plane wave migration method is superior to plane wave migration achieved through the two-step method based on the wave equation datum. Migration results set for smoothing imaging condition are significantly better than the results of cross correlation imaging condition. This paper also gives the comparative results with different smoothing operators, and so provides a theoretical basis for the practical application of this approach.
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