Abstract:Wave equation-based continuation approach keeps the feature of dynamics and kinematics of wavefield,can better overcome the shortcomings of time-shift static correction approach that distorts wavefield and eliminate the influence of relief surface,and reforms records in non-horizontal surveying interface to that in horizontal surveying interface (new datum).Synthesis of plane wave source and its records in reconstructive horizontal datum can overcome the issues that is incapable to synthesize the plane wave source and its records because of relief geomorphology,finishing plane wave migration in relief surface condition.In order to further improve operation efficiency,and according to the principle distributing the plane waves in different incident angles and frequency range to separate nodes,the MPI parallel computation was implemented,which doubled and redoubled the computational efficiency.The concrete steps are as follows: continuing the CSP gathers to new datum that is below the lowest relief plane; ②sorting CRP gathers from continued CSP gathers data; ③continuing the CRP gathers to new datum that is below the lowest relief plane; ④sorting CSP gathers from CRP gathers continued to new datum.The total abovementioned process corresponds to downshift the geometry to new datum.The results of model tests and practical data processing showed that the results of parallel plane wave depth migration after reconstruction of datum are same as that of depth migration data by directly down-continuing wavefield based on raw shot records,but the former computational efficiency doubled and redoubled along with increasing the number of applied nodes.