地震波速与吸收系数综合层析成像

The seismic tomography of combining velocity and absorption coefficient

阐述了地震波在粘弹性介质传播过程中具有的衰减特性,探讨了地震波吸收层析成像的机理,得知地震吸收CT成像方法,对岩体软弱结构面、裂隙和规模较小的断层破碎带的识别能力,要强于波速成像方法.针对这两种层析技术的优缺点,采取多参数(波速、吸收系数)综合地震层析成像的方法,使波速CT与吸收CT两者能相互印证、互为补充.作者综合利用两种成像方法,把它用于在云南省某水电站坝基岩体质量检测中,取得了较好的效果,达到了提高地震层析成像的分辨率与可靠性的目的.

At first, this article expounds the attenuation characteristic of earth wave when it diffuses in the viscoelasticity medium. And at the same time, through discussing the mechanism of earth wave absorbing tomography, it is known the CT of seismic absorption imaging method is better than the wave velocity imaging method in the identify aT bility of faultage crushed zone whose body structural plane is flabbiness and the dimensions is small. According to the advantage and disadvantage of the two seismic tomography technology, we could take multiparameter integrate seismic tomography imaging method to confirm and makeup the the velocity CT and the absorption CT each other. The author combines this two imaging method, and applies to the quality detection of one hydroelectric installation in YunNan province. The effect is well, and attains the goal of improving the resolution and reliability of the seismic tomography.