用面波反演风化层Q值──补偿风化层吸收提高分辨率

Inversion of quality factor Q for weathered layer using surface waves──Compensating seismic wave absorption in weathered layer to increase resolution

长春地质学院, 长春130026

Department of Exploration Geophysies, Changchun College of Deology, Changchun 130026

风化层对地震波的强烈吸收作用导致地震记录分辨率降低。根据粘弹波动理论,这种吸收作用相当于线性时不变滤波。对地震记录进行吸收的补偿处理可以提高分辨率,为此,需要反演风化层的Q值。本文利用面波来反演风化层的Q值。由于本方法考虑到噪声的存在,其抗噪能力较强。文章给出了实际资料的处理结果。

The seismic wave absorption in weathered layer is strong, causing the resolution of seismicdata to be low. Accotding to the viscoelastic wave theory, this absorption effect is equivalent to alinear time-invariant filtering. Compensation of the absorption can increase the resolution ofseismic data. For this reason, the inversion of Q-value for weathered layer is necessary. Thispaper makes use of surface waves to find Q-Value in weathered layer. This method takes accountof the presence of noises, thus increasing greatly the reliability of Q-value obtained. Theprocessing result on real data is presented.