Finite-difference solution of the eikonal equation using an efficient, first-arrival, wavefront tracking scheme
Finite-difference solution of the eikonal equation using an efficient, first-arrival, wavefront tracking scheme
复制标题
DOI：
10.1190/1.1443623
复制
发表时间：
1994-04
期刊：
影响因子：
3.3
通讯作者：
S. Cao;S. Greenhalgh
中科院分区：
文献类型：
--
作者：
S. Cao;S. Greenhalgh
初至波旅行时可以通过程函方程的有限差分解使用新的角节点离散格式来精确计算。与传统的以单元为中心的节点方案相比，它具有精度优势。一个显着的效率提高是通过结合波前跟踪算法的基础上构建的最小走时树。对于传统的离散方案，一个准确的平均值的本地平方慢度被发现是至关重要的稳定的数值方案的模型与大慢度对比。基于传统离散化方案的改进方法可用于计算任意变化速度模型中的走时，但基于角节点离散化方案的方法提供了更好的解决方案。
First‐break traveltimes can be accurately computed by the finite‐difference solution of the eikonal equation using a new corner‐node discretization scheme. It offers accuracy advantages over the traditional cell‐centered node scheme. A substantial efficiency improvement is achieved by the incorporation of a wavefront tracking algorithm based on the construction of a minimum traveltime tree. For the traditional discretization scheme, an accurate average value for the local squared slowness is found to be crucial in stabilizing the numerical scheme for models with large slowness contrasts. An improved method based on the traditional discretization scheme can be used to calculate traveltimes in arbitrarily varying velocity models, but the method based on the corner‐node discretization scheme provides a much better solution.