地震背景噪声互相关的尾波互相关(C;)研究进展

Research progress on correlation of the coda of the correlation(C;)from ambient seismic noise

背景噪声地震学是近些年地震学研究的热点领域,其理论基础是背景噪声的互相关(C^(3))与台站间经验格林函数的等价关系.进一步的研究发现,从噪声互相关尾波的互相关(C^(3))中也可以提取经验格林函数.本文系统地综述了目前国内外在背景噪声C^(3)方面的研究进展.首先介绍了C^(3)计算方法的研究进展和对互相关波形对称性改善的特性.之后重点评述了C^(3)方法在地下结构成像和介质时变监测方面的进展:C^(3)方法可以得到不同观测时间的台站对间的面波频散信息,充分利用了不同期次的观测台阵的数据;C^(3)方法得到的地下波速时变监测结果与C^(3)方法基本一致,将C^(3)和C^(3)结合,有助于提升地下结构成像和监测结果的分辨率和可靠性.最后展望了背景噪声C^(3)方法的研究前景.

Ambient noise seismology is a hot field of seismology research in recent years.Its theoretical basis is the equivalence relationship between the cross-correlation of ambient noise(C^(3))and the empirical inter-station Green’s function.Further research found that the empirical Green’s function can also be extracted from correlation of the coda of the correlation(C^(3))of ambient seismic noise.This paper systematically reviews the current domestic and foreign research progresses on ambient noise C^(3).Firstly,the research progress of C^(3)process method and the improvement of symmetry of cross-correlation waveform are introduced.Afterwards,we focus on the progress of C^(3)method in ambient noise tomography and noise-based monitoring:C^(3)method can be used to obtain the surface wave dispersion information between pairs of stations at different observation times,and it makes full use of the data of observation arrays at different periods;the noise-based monitoring results of underground seismic velocity obtained by C^(3)method are basically the same as those of C^(3)method.Combining C^(3)and C^(3)will help improve the resolution and reliability of ambient noise tomography and monitoring results.Finally,the research prospects of the ambient noise C3 method are prospected.