伪谱法分离波动方程弹性波模拟  

Elastic wavefield simulation using separated equations through pseudo-spectral method

作　　者：唐小平[1] 白超英[2] 刘宽厚[1] 

机构地区：[1]中国地质调查局西安地质调查中心,陕西西安710054 [2]长安大学地测学院地球物理系,陕西西安710054

出　　处：《石油地球物理勘探》2012年第1期19-26,188+192,共8页Oil Geophysical Prospecting

基　　金：国家地质调查项目(1212011120917)资助

摘　　要：本文在一阶分离波动方程的基础上,推导出了相应的二阶分离波动方程的简单形式。采用交错网格和常规网格伪谱法,实现了一阶及二阶波动方程波场P波和S波的分离模拟。同时对一阶、二阶波场分离模拟结果,以及分离法与非分离法模拟结果进行了对比研究。结果表明:一阶与二阶伪谱法分离的效果大致相当,一阶分离法在走时拾取上略占优势,但二阶分离法在振幅和子波形态保护及分离彻底性方面优势明显;实际计算中分离法比非分离法更为灵活多变。Based on the first order wave equation separation,the similar formula for second-order wave equation separation method is deduced in this paper,which has a simple form and easy derivation over the original one.The separated first-and se-cond-order wave equation is solved with regular-and staggered-grid pseudo-spectral method.As a result,the P and S wavefield can be obtained directly.Comparing with the first-order and the second-order pseudo-spectral method,and separation and non-separation method,our results show that the first-order and second-order pseudo-spectral methods have same effect in wavefield simulation,but first-order one is good at the traveltime picking,while the second-order one is advantageous over the first-order one in terms of the wavelet amplitude preservation,waveform protection and wavefield separation.The wavefiled separation simulation method has more flexible usage in computation projection.

关 键 词：分离法波场模拟 一阶伪谱法 二阶伪谱法 交错网格 规则网格 

分 类 号：P631[天文地球—地质矿产勘探]