摘要
地震勘探中,面波通常具有低频、低速、强能量的特征,会干扰有效波,降低地震数据的信噪比,在地震处理中通常作为噪声予以压制。但由于面波具有频散的特性,能够反映近地表的结构特征,因此面波可以"变废为宝"进行近地表速度的估计。本文首先采用相移的方法对面波数据进行频散分析,提取频散曲线,然后利用加权阻尼最小二乘反演的方式去拟合拾取的频散点,进而获得该道的横波速度。最后通过模型和实际数据验证了本文方法的有效性。
引文
[1]董烈乾,李振春,王德营等.第二代Curvelet变换压制面波方法.石油地球物理勘探,2011,46(6):897-904.
[2]Yan,J.,F.J.Herrmann,2009.Ground-roll prediction by interferometry and separation by curvelet-domain matched filtering.79th Annul International Meeting,SEG Expanded Abstracts,3297-3301.
[3]Park C B,Miller R D,Xia J.Multichannel analysis of surface waves.Geophysics,1999,64:800-808.
[4]Xia,J.,R.D.Miller,and C.B.Park,1999.Estimation of near-surface shear-wave velocity by inversion of Rayleigh waves.Geophysics,64,no.3,691-700.
[5]Xia,J.,R.D.Miller,and C.B.Park,G Tian,2003.Inversion of high frequency surface waves with fundamental and higher modes.Journal of Applied Geophysics,52,no.1,45-57.
[6]Knopoff L.A matrix method for elastic wave problems.Bulletin of Seismological Society of America,1964,54:431-438.