改进的FCT方法在粘滞各向异性介质地震波模拟中的研究  

Study on seismic wave simulation of viscous anisotropic media using the improved FCT method

作　　者：李勤武 周怀来[1,2,3] 

机构地区：[1]成都理工大学地球物理学院,成都610059 [2]成都理工大学油气藏地质及开发工程国家重点实验室,成都610059 [3]成都理工大学地球探测与信息技术教育部重点实验室,成都610059

出　　处：《物探化探计算技术》2016年第1期74-82,共9页Computing Techniques For Geophysical and Geochemical Exploration

基　　金：国家自然科学基金(41204091)

摘　　要：在地震勘探中,粘弹性各向异性介质相比弹性介质更能实际表征地下介质的性质,这里主要针对Kelvin模型从本构方程、几何方程和运动微分方程,推导其一阶应力速度方程,运用交错网格有限差分法对其进行数值模拟,研究该介质中地震波的波场特征与传播规律。同时分析了品质因子Q对地震波在振幅以及频率上的衰减、吸收作用的影响。在数值模拟中,使用交错网格算法必然会造成数值频散或假频现象,从而干扰数值模拟结果的正确性。为了提高数值模拟效果,对常规FCT(通量校正传输法)方法进行优化来压制频散,模拟实例证明,优化后的FCT方法要比常规FCT方法在消除频散方面更加有效,能有效地改善数值模拟精度。Compared to elastic media,the viscoelastic anisotropic media is more practical subsurface characterization in seismic exploration.In this paper mainly aimed at the Kelvin model,Derived the first order stress velocity equation from constitutive equations,geometric equations and differential equations.Then,the numerical simulation of the staggered grid finite difference is used to discrete it and research wave field characteristics and propagation of seismic waves.At the same time,the analysis of the influence of quality factor Q on the attenuation and absorption of seismic wave in amplitude and frequency.Use staggered grid algorithm would inevitably result in numerical dispersion or aliasing phenomenon in numerical simulation,and thus the correctness of the results of the numerical simulation is disturbed.In order to improve the results of numerical simulation,optimized the conventional FCT（flux corrected transport）method to suppress dispersion.Simulation examples demonstrate that the optimized FCT method is more effective than the conventional FCT method in eliminating frequency dispersion.

关 键 词：KELVIN模型 一阶应力速度方程 数值模拟 品质因子Q 优化后FCT方法 

分 类 号：P631.4[天文地球—地质矿产勘探]