CAJ | 학술논문

从双程声波方程出发,在交错网格空间中推导了地震波逆时延拓的高阶有限差分算子,依据最佳匹配层(PML)的方程分裂思路,得到了一阶声波方程的PML边界条件及其高阶差分格式,采用零时间成像条件和上行、下行波场互相关成像条件,实现了声波方程的叠后与叠前逆时深度偏移.逆时偏移对sigsbee_2b模型理论数据的偏移成像得到了满意效果.
종쌍정성파방정출발,재교착망격공간중추도료지진파역시연탁적고계유한차분산자,의거최가필배층(PML)적방정분렬사로,득도료일계성파방정적PML변계조건급기고계차분격식,채용령시간성상조건화상행、하행파장호상관성상조건,실현료성파방정적첩후여첩전역시심도편이.역시편이대sigsbee_2b모형이론수거적편이성상득도료만의효과.
Based on two-way acoustic wave equations, a high-order finite difference reverse-time propagation scheme is established using a high precision operator in staggered-grid, and a perfectly matched layer(PML) absorbing boundary conditions is also proposed in the paper which can be computed by the same finite different scheme. Based on above two techniques, the post-stack and pre-stack reverse-time depth migrations of compression seismic wave are achieved by using a zero time imaging condition in post-stack migration and an exciting time imaging condition in pre-stack migration. The processing of synthetic data of sigsbee_2b model obtained a satisfactory result.