分离纵波和横波的偏振旋转法
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摘要
本文依据地震波的偏振特征和最小化方法，由三分向记录的协方差矩阵的特征值确定偏振参数（椭圆率、线性因子等），设定旋转记录的滤波因子、增强有效信号和压制面波等干扰信号；并由协方差矩阵的特征向量确定不同偏振波性质（纵波、横波等）及其旋转方向；建立新的线性组合，把纵波旋转到垂直分量，按其偏振特点与传播方向间的关系把两个横波分别旋转到径向和切向分量，最终得到纵波、横波分离的记录和偏振参数（椭圆率角、主偏振平面）．从新构成的图像能够有效地识别地震记录中的横波震相及横波分裂．
According to polarizing characterisyics of seismic waves and least square methods, the po larizing psrameters (ellipse rate,linear coefficient etc. ) and factor of polarizing filter are defined by eigenvalue of variance-covariance matrix of three component records,the efficient signal are strengthened and disturbance signal are suppressed. Then properties of different polarizing waves (P and S-waves) and revolving direction of new records arc defined, new linear combi nations are built by eigenvectors of variance-covariance matrix. P-waves are revolved to vertical Component, and tow S-waves are revolved to horizontal components by relation between polarizing properties of seismic waves and observational system. Finally, three new records of P and S-waves separated, the polarizing parameter (ellipse rate angle, main polarization plane etc.) are obtained. S-waves and S-wave splitting in seismic records can be effectively distinguished from new built diagrams.
According to polarizing characterisyics of seismic waves and least square methods, the po larizing psrameters (ellipse rate,linear coefficient etc. ) and factor of polarizing filter are defined by eigenvalue of variance-covariance matrix of three component records,the efficient signal are strengthened and disturbance signal are suppressed. Then properties of different polarizing waves (P and S-waves) and revolving direction of new records arc defined, new linear combi nations are built by eigenvectors of variance-covariance matrix. P-waves are revolved to vertical Component, and tow S-waves are revolved to horizontal components by relation between polarizing properties of seismic waves and observational system. Finally, three new records of P and S-waves separated, the polarizing parameter (ellipse rate angle, main polarization plane etc.) are obtained. S-waves and S-wave splitting in seismic records can be effectively distinguished from new built diagrams.
引文
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