2.5维各向异性介质中多波波场正演模拟与波场分析  

2.5D MULTIWAVE WAVE FIELD FORWARD SIMULATION AND WAVE FIELD ANALYSIS IN ANISOTROPY MEDIA

作　　者：苏云[1] 李录明[1] 唐娟[1] 

机构地区：[1]成都理工大学信息工程学院,四川成都610059

出　　处：《物探与化探》2010年第2期262-266,共5页Geophysical and Geochemical Exploration

基　　金：教育部博士点基金(20070616004)资助

摘　　要：完全3维弹性波数值模拟计算时间长,并且占用庞大的计算资源,这不利于在计算机配置不高的情况下进行科学研究,而二维弹性波数值模拟又达不到三维模拟的精度;同时,当模型、波场空间分布比较复杂时,传统的3维波动方程拟谱法模拟结果比较差。因此,在较高数值精度的一阶应力—速度弹性波动方程的基础上,采用傅氏变换仅计算y方向的偏导数,利用有限差分方法计算x、z方向和时间的偏导数,即利用2.5维数值模拟方法,实现在二维介质中计算三维弹性波场。最后通过数值模拟实现了在各向异性介质中多波波场的数值模拟,验证了2.5维方法是一种高精度、高效率、且能适应复杂模型的正演模拟方法,通过波场分析进一步认识了波在各向异性介质中的传播规律。Pure 3D elastic wave numerical simulations require huge computation resources, which is not conducive to scientific research when computer configuration is not high. 2D elastic wave numerical simulation cannot accurately represent 3D situation, and the simulation results are relatively unsatisfactory by using the traditional 3D pseudo spectral method when the model and spatial distribution of wave field are complex. Thus, based on high accurate one-order elastic wave equation expressed with velocity and stress, this paper u- ses 2.5D numerical simulation method to calculate the partial derivatives of y spatial orientation by Fourier transforming and the partial derivative of x, y spatial orientation and time domain by finite difference. This method can hence compute the 3D elastic wave field in 2D media. This paper also simulates the multiwave wave field in anisotropy media using 2.5D numerical simulation method, which shows that the 2.5D numerical simulation method is an efficient and accurate forward method. This method can also be adapted to complex models. Through wave field analysis, the authors further understand the propagation law of the seismic wave in anisotropy media.

关 键 词：2.5维各向异性 弹性波 傅氏变换 有限差分 数值模拟 

分 类 号：P631.4[天文地球—地质矿产勘探]