利用背景噪声进行地震成像的新方法

A new method for seismic imaging from ambient seismic noise

利用背景地震噪声提取格林函数,即通过一对台站记录的地震噪声进行互相关计算,来近似台站间的格林函数,并进一步通过地震成像获取地下结构的认识,成为最近跨学科研究的热点问题之一.本文首先叙述了其发展背景及过程,然后分别从四个角度,简要介绍了目前对其物理原理的解释.如果该方法能得到进一步的发展,将不再依赖于天然地震以及人工地震,而仅仅利用地震台站记录的地震噪声便可获取高分辨率的地下成像.该方法将会大大促进地震学的发展.

Recently, one of the hotly discussed problems in multidisciplinary fields is to use ambient seismic noise to extract the Green＇s function, i. e. , cross-correlating the seismic noise recorded by two stations to get the Green＇s function between these two stations, thus to improve our knowledge about subsurface structures by use of seismic imaging. In this paper, the developing background and process of this new method will be introduced firstly. And then its physical principle will be also shown from four different viewpoints. If this method could be developed more, seismic images with high resolution will be acquired without natural earthquakes or artificial explosions, but just the seismic ambient noise. This new method may greatly advance the development of seismology.