3D wavefield extrapolation with optimal separable approximation  

作　　者：Zhang Zhifu Meng Xiaohong Liu Hong Chen Jingbo Li YouMing 

机构地区：[1]State Key Laboratory of Geological Processes and Mineral Resources, ChinaUniversity of Geoscienees, Beijing 100083, China [2]Geo-detection Laboratory, Ministry of Education of China, China University of Geosciences, Beijing 100083, China [3]Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China

出　　处：《Applied Geophysics》2006年第4期218-225,共8页应用地球物理（英文版）

基　　金：This research is sponsored by China National Natural Science Foundation （N0. 40474047）.

摘　　要：An accurate and wide-angle one-way propagator for wavefield extrapolation is an important topic for research on wave-equation prestack depth migration in the presence of large and rapid velocity variations. Based on the optimal separable approximation presented in this paper, the mixed domain algorithm with forward and inverse Fourier transforms is used to construct the 3D one-way wavefield extrapolation operator. This operator separates variables in the wavenumber and spatial domains. The phase shift operation is implemented in the wavenumber domain while the time delay for lateral velocity variation is corrected in the spatial domain. The impulse responses of the one-way wave operator show that the numeric computation is consistent with the theoretical value for each velocity, revealing that the operator constructed with the optimal separable approximation can be applied to lateral velocity variations for the case of small steps. Imaging results of the SEG/EAGE model and field data indicate that the new method can be used to image complex structure.为波浪领域推测的一个精确、宽角度的单程的增殖者面对大、快速的速度变化是为关于波浪方程 prestack 深度移植的研究的一个重要话题。基于在这篇论文介绍的最佳的可分离的近似，有前面、反的 Fourier 变换的混合的域算法被用来构造 3D 单程的波浪领域推测操作员。这个操作员在波浪号码和空间领域分开变量。当为侧面的速度变化的时间延期在空间领域被改正时，阶段移动操作在波浪数字领域被实现。单程的波浪操作符的推动回答证明数字计算与为每速度的理论值一致，表明与最佳的可分离的近似构造的操作符能被用于为小步的盒子的侧面的速度变化。SEG/EAGE 模型和领域数据的成像结果显示新方法能习惯于图象建筑群结构。

关 键 词：WAVE-EQUATION optimal separable approximation one-way wavefield extrapolation operator SYMBOL prestack depth migration. 

分 类 号：P3[天文地球—地球物理学]