用微动中的面波信息探测地壳浅部的速度结构

To determine the velocity structure of shallow crust with surface wave information in microtremors

本文介绍了利用地脉动中的面波信息探测地壳浅部横波速度结构的观测方法、仪器设备、野外数据采集和用空间自相关方法测定相速度及相关的数据处理方法，并给出了在两个场地的探测实例．通过与钻探结果对比表明，由该方法推测的地壳浅部1—2km深度范围的浅层横波速度结构，对于确定物性差异大的地层界面是有效和可靠的．由于该方法使用的是地脉动噪声中的面波信息，不需要专门的震源，因此具有经济快捷、应用范围广泛等优点，将可能成为一种新的具有很好应用前景的地球物理勘探方法．

This paper presents the method of using surface wave information in microtremors to study the Swave velocity structure of shallow crust. It introduces the observation method, instruments, field data acquisition, the method of using autocorrelation to determine phase velocity and relevant data processing methods, it also shows detecting cases at two sites. The comparison with bore-hole results shows that the velocity structure of shallow crust within the depth of 1 - 2 km obtained by this method is effective and reliable for the strata interfaces which have great physical differences. Because this method uses surface wave information in microtremors without any special source, it is much more economic, faster and more widely applicable, and it will probably be a new kind of geological prospecting methods with good application prospect.