粘弹介质中可变网格地震波传播数值模拟

Variable-grid numerical simulation of seismic wave propagation in visco-elastic media

(同济大学海洋地质国家重点实验室,上海200092)

Li Xiaobo,State Key Laboratory of Marine Geology,Tongji University,Shanghai 200092,China

从Kelvin介质的本构方程出发推导了粘弹介质中的弹性波方程和声波方程,建立了粘滞弹性波方程的交错网格高阶差分解和粘滞声波方程的高阶差分解,并应用可变空间网格与局部可变时间步长数值计算技术,形成了适用于粘弹介质中弹性(声)波传播的高效、高精度的数值模拟方法。数值实验结果表明,该方法可以有效模拟地震波在粘弹介质中的传播,并且可以比较准确地刻画精细介质结构,在保证模拟精度的同时极大地提高了计算效率。

Li Xiaobo,Dong Liangguo.GPP,2012,51(1): 1~10
Starting from the constitutive equation of the Kelvin media,the viscoelastic and visco-acoustic wave equation were derived,and Staggered-Grid High Order Finite Difference solutions for viscoe lastic wave equation were established.Meanwhile,by applying variable spatial grid and locally variable time step,a high-efficiency and high-precision numerical simulation method were achieved for the propagation of elastic(acoustic) wave in viscoelastic media.The numerical simulation results indicate that the methods can effectively simulate the propagation of seismic wave in the viscoelastic media.Furthermore,the methods can accurately characterize the fine structure of the media and greatly improve the computation efficiency while preserving simulation precision.

10.3969/j.issn.1000-1441.2012.01.001