基于完全三叉树的快速推进法地震波走时计算

快速推进法(简称FMM)在地震波走时计算中有着精度高、效率高的特点,但窄带扩展每次都要寻找最小走时。当网格节点较多时,寻找最小走时非常耗时。在保证精度的前提下,为了提高计算效率,笔者对堆排序的排序方式做了改进,将完全三叉树排序方法引入到快速推进法地震波走时计算中。模型试算结果表明,基于完全三叉树快速推进法计算出的地震波走时与用完全二叉树方法的精度一致,且前者比后者效率提高约10%。

Computation of fast marching method on seismic wave travel- time based on complete ternary tree

In seismic wave travel- time calculation，fast marching method (FMM) has the characteristics of high precision and efficiency，but its narrow band extension has to find the minimum travel- time for every time， which is very time consuming which when the grid nodes are massive． On the premise of guarantee accuracy，the authors made improvements on the heap sorting method，and introduced complete ternary tree heap sorting method into FMM of seismic wave travel- time calculation in order to improve the computational efficiency． The experimental results show that seismic wave travel- time calculated by FMM based on complete ternary tree has the same precision with FMM based on complete binary tree one，and the former is higher in efficiency than the latter，which increases by about 10%。