利用时频域极化滤波压制地震面波  

Seismic surface wave suppression with polarization filtering method in time-frequency domain

作　　者：马见青[1] 李庆春[1] 

机构地区：[1]长安大学地质工程与测绘学院,陕西西安710054

出　　处：《石油地球物理勘探》2015年第6期1089-1097,1031,共9页Oil Geophysical Prospecting

基　　金：国家自然科学基金项目(41374145;41004043);高等学校博士点基金项目(20120205130002);中央高校基金项目(2013G1261060)联合资助

摘　　要：把时频分析方法和自适应协方差矩阵方法结合起来,提出了一种压制地震面波的时频域极化滤波方法。该方法在广义S变换时频方法的基础上,构建时频域自适应协方差矩阵,通过特征分析计算时频域瞬时极化参数,设计极化滤波器,实现多分量地震面波压制。其优势在于可以根据信号的瞬时频率将协方差矩阵的分析时窗长度自适应地选择为每个时频点处的波的优势周期,在每个时频点估计特征参数,无须进行插值。模型数据及实际三分量地震数据处理结果表明,该极化滤波方法在压制地震面波方面具有较高的分辨率。In seismic exploration,surface wave is considered as a noise,and needs to be suppressed.We propose in this paper a surface wave suppression method with polarization filtering based on the generalized S transform.On one hand,we remould the window function of S transform,and improve the frequency resolution of seismic signal by increasing the regulatory factors to implement nonlinearly variable window function with the frequency.On the other hand,we construct the cross-energy matrix in time-frequency domain using the generalized S transform,compute instantaneous polarization attributions through eigenanalysis and design filter algorithm in the time-frequency domain to achieve multi-component seismic polarization filtering.The specialties of this method are that the time window length of covariance matrix is determined by the instantaneous frequency of multi-component seismic data.And it can adapt with the dominant period of the desired signal.Meanwhile,it calculates polarization parameters at each time-frequency point and no longer needs to undertake the interpolation.Processing results of model data and real three-component data show that surface wave is well removed by the proposed method,and high resolution data is obtained.

关 键 词：极化滤波 时频域 自适应 协方差矩阵 瞬时频率 广义S变换 

分 类 号：P631[天文地球—地质矿产勘探]