最佳差分算子在P-SV波正演模拟中的应用

OPTIMUM DIFFERENCE OPERATOR APPLIED TO P - SV WAVE FORWARD SIMULATION

1. 哈尔滨工业大学博士后力学站,哈尔滨150000;2. 成都地质学院,成都610059

1. Post - doctor mechanics station, Harbin industrial university, Harbin 150000;2. Cheng Du college of geology, Chengdu 610059

本文提出用最佳差分技术模拟在二维非均匀介质中传播的P-SV波。只要这种方法的差分算子半长度取成4—6,每最短波长取3个空间网格点就可得到精度很高的弹性波正演模拟结果。用最佳差分算子模拟P-SV波的计算速度比用传统差分格式至少快一个数量级,比目前公认的速度较快的伪谱法还要快3—5倍。

This paper suggests that a P-SV wave traveling in a 2-D inhomogeneous medium could be simulated with an optimum difference operator when the halflength of the difference operator is taken to be 4 to 6 grid interval, three grid interval per shortest wavelength will do to yield high accuracy results for elastic wave’s forward modeling. Velocity computation using optimum difference operator to simulate P-SV waves is at least one order of magnitude faster than using conventional finite difference schemes and 3 to 5 times as fast as the pseudospectral method which is currently accepted to be the fastest one.