Quasi‐spherical approach for seismic wave modeling in a 2‐D slice of a global Earth model with lateral heterogeneity
Quasi‐spherical approach for seismic wave modeling in a 2‐D slice of a global Earth model with lateral heterogeneity
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DOI：
10.1029/2004gl022180
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发表时间：
2005-05
影响因子：
5.2
通讯作者：
G. Toyokuni;H. Takenaka;Yanbin Wang;B. Kennett
中科院分区：
文献类型：
--
作者：
G. Toyokuni;H. Takenaka;Yanbin Wang;B. Kennett
为了在有限的计算机资源下进行合成地震记录的迭代计算，需要一种快速、准确的模拟方法。在全球地震学中经常使用轴对称模型来限制计算时间和存储。这种方法可以正确地模拟三维几何扩散效应，计算时间与二维方法相当，但不能处理关于源轴的非对称结构。为了克服这个问题，提出了一种新的方法，通过具有横向非均匀性的全球地球模型，在二维切片中进行地震波传播。球坐标下的弹性动力学方程不是在传统的球域中求解，而是在“准球域”中使用有限差分法求解。包括俯冲带结构的数值例子说明了这种技术的有效性和效率。
For iterative calculations of synthetic seismograms with limited computer resources, a fast and accurate modeling method is needed. Axisymmetric modeling has often been used in global seismology to restrict computational time and storage. This approach can correctly model 3‐D geometrical spreading effects with computational times comparable to 2‐D methods, but cannot treat asymmetric structures about the source axis. To overcome this problem, a new approach is proposed for seismic wave propagation in a 2‐D slice through a global Earth model with lateral heterogeneity. The elastodynamic equation for spherical coordinates is not solved in the conventional spherical domain but instead in the “quasi‐spherical domain” using the finite‐difference method. The validity and efficiency of this technique is illustrated with numerical examples including subduction zone structures.