中文摘要：

本文较为系统综述了国内外在不均匀介质中各种主要和实用的射线追踪方法，例如：基于射线理论的打靶法、弯曲法（伪弯曲法）、高斯射线束算法等；基于网格单元扩展的有限差分解程函方程法（FD）、最短路径算法（SPM）；以及结合射线和网格单元扩展的波前构造法等．同时对目前出现的多次波射线追踪技术、以及多值波前追踪技术（如：相空间算法、水平集算法）也进行了分析讨论．同时对基于网格单元扩展算法的优缺点进行了评述，其基本结论是：基于单元模型的SPM要优于FD算法，而基于网格的SPM算法则次之．就传统的射线追踪算法（如：打靶法和弯曲法）而言，其未来的发展方向是实现完全非线性的相应算法，而基于网格单元的算法则主要是扩展功能（如：后续波、多值波前的追踪）．射线追踪方法技术未来需要解决的问题主要有：块状模型中多次波的追踪；多值波前及多值射线追踪；走时与振幅的同时追踪计算；以及其它领域新方法的引入．

英文摘要：

In this paper we focus on the review of main and practical seismic ray tracing algorithms in complex media,which includes the ray based method, such as the shooting method, the bending method（or pseudo bending method）and the Gaussian beam method; the grid cell based method, such as the finite-difference Eikonal equation solver（FD）and the shortest-path method（SPM） ;the combined method, such as the wavefront construction method. Meanwhile,we also discuss some current algorithms for muhiple arrival tracking and multi-valued wavefront tracing （e g,the level set method and the phase space method）. Based on the previous researches, we compare the grid-cell based methods and conclude that the cell-based SPM is superior to the FD algorithm, and the grid-based SPM is less favorable choice in term of computational efficiency. For the traditional ra~based algorithm （e g, shooting and bending method）, it will concentrate on the full non-linear algorithm; while for the grid-cell based algorithms, they will focus on the extension of the functional（such as,later arrival tracking and multi-valued wavefront tracing）. The future emphases in seismic ray tracing may include： multiple arrival tracking methods in block model, efficient multi- valued wavefront tracing algorithms; methodologies for simultaneous calculation of the traveltime and amplitude information and introduction of model algorithms from other fields（ for example, computing mathematics）.