摘要
本文基于Alkhalifah的P-SV波频散关系,应用声波近似假设推导了横向各向同性介质(TI)中的声波标量方程组,其中每个方程都含有与时间和空间有关的二阶导数项,并且方程中不含有混合导数项,易于利用有限差分法进行数值模拟。文中采用改进的不完全声波近似假设,从而获得了更长的稳定模拟时间,与采用传统声波近似假设相比,波场传播更加稳定。有限差分数值模拟及复杂模型数据的计算结果表明,TI介质中的声波标量方程组能准确地描述准声波在TI介质中的运动学特征,能很好地进行逆时偏移成像。
Based on Alkhalifah's P-SV dispersion relation in VTI media,we apply in this paper pseudo-acoustic approximate to derive the acoustic scalar equations in transversely isotropic(TI) media.Each of these equations is second-order derivative in time and space with no mixing of time and space derivatives,which makes it easier and more efficient to realize finite difference method numerical simulation.Using improved incomplete pseudo-acoustic approximate,we obtain a longer stability simulation time.Wavefield simulation process is more stable compared with the conventional pseudo-acoustic approximation method.Both the finite difference numerical simulation and the complex model test show that the derived pseudo-acoustic scalar equations could accurately describe kinema-tics characteristic of P wave in TI medium,which facilitate efficient anisotropic RTM.
出处
《石油地球物理勘探》
EI
CSCD
北大核心
2012年第4期573-577,682+513,共5页
Oil Geophysical Prospecting
关键词
逆时偏移
TTI介质
声波近似假设
有限差分
reverse time migration(RTM),TTI media,pseudo-acoustic approximation,finite difference method
