| 基于完全三叉树堆排序的波前扩展有限差分地震波走时快速算法 |
| |
| 引用本文： | 杨昊,孙建国,韩复兴,马淑芳.基于完全三叉树堆排序的波前扩展有限差分地震波走时快速算法[J].吉林大学学报(地球科学版),2010,40(1):188-194. |
| |
| 作者姓名： | 杨昊 孙建国 韩复兴 马淑芳 |
| |
| 作者单位： | 中国石油勘探开发研究院,北京,100083;吉林大学,地球探测科学与技术学院/国土资源部应用地球物理综合解释理论开放实验室,长春,130026 |
| |
| 基金项目： | 国家自然科学基金项目(40574052);;教育部骨干教师资助计划项目(2000-06) |
| |
| 摘 要： | 波前扩展有限差分地震波走时算法具有物理意义明确、因果稳定性强的特点,但每次波前扩展都要寻找波前面上的最小走时点。当计算网格点数较多,特别是涉及到三维走时计算时,寻找波前面上的最小走时点是一项十分耗时的工作。研究发现,波前扩展有限差分地震波走时算法的波前点具有两个突出特点:①波前点更新十分频繁,通常每次取出波前最小走时点后都要插入若干新的波前点;②新计算出的波前点的走时通常比较大。数据结构中的二叉树堆排序方法可以提高寻找波前面上最小走时点的效率,根据特点①,在原始二叉树堆排序方法的基础上,优化了插入新波前点和移除波前面上最小走时点的流程,实际计算结果表明,与原始的二叉树堆排序方法相比,改进后的二叉树堆排序方法可以提高大约20%的计算效率。根据特点②,将原始的二叉树堆排序方法推广到多叉树,实际计算结果表明,完全三叉树堆排序方法优于二叉树和四叉树堆排序方法,可以再提高5%的计算效率。
|
| 关 键 词： | 走时 波前扩展 程函方程 堆排序 有限差分法 |
Fast Algorithm of the Expanding Wavefronts Finite-Difference Traveltime Calculation Based on the Three Branch Tree Structure Heap Sorts |
| |
| YANG Hao,SUN Jian-guo,HAN Fu-xing,MA Shu-fang.Fast Algorithm of the Expanding Wavefronts Finite-Difference Traveltime Calculation Based on the Three Branch Tree Structure Heap Sorts[J].Journal of Jilin Unviersity:Earth Science Edition,2010,40(1):188-194. |
| |
| Authors: | YANG Hao SUN Jian-guo HAN Fu-xing MA Shu-fang |
| |
| Abstract: | Traveltime calculation using the expanding wavefronts finite-difference method is characterized by its explicit physics meanings and causal stabilities, but the method needs to search the minimum traveltime point frequently when expanding the wavefront. The method becomes more time consuming when there are too many grid nodes, particularly for 3D calculation. Two main characteristics of the wavefront points are found through this study: ①The wavefront points is updated frequently. Generally several new points are inserted to the wavefront points set after the minimum traveltime point is removed. ②The traveltime of new calculated wavefront point is often larger than that of others. The authors try to improve the efficiency of traveltime calculation by using the binary tree structure heap sorts. According to the first characteristic of the wavefront points, the original binary tree structure heap sorts is ameliorated in that the inserting and removing operations on the heap is optimized which improves the calculation efficiency by about 20%. From the second characteristic of the wavefront points, three branch structure heap sorts is introduced which improves the calculation efficiency by another 5%. |
| |
| Keywords: | traveltime expanding wavefronts eikonal equation heap sorts finite difference method |
| 本文献已被 CNKI 万方数据 等数据库收录！ |
|
