基于瑞雷波法的成都盆地场地剪切波速结构确定

在2008年的汶川地震中获得了大量的有价值数据和资料,使得成都盆地成为了研究的热点.为了能够获得成都盆地场地剪切波速结构,为成都盆地及汶川地震的进一步研究提供基本数据支持,本文利用多道面波分析方法在成都盆地(E:103°～105°,N:30°～32°)布置了40个面波测点进行场地剪切波速结构和覆盖层厚度的调查,测点间距...

Multi-channel analysis of surface wave method based determination of S-wave velocity structure of Chengdu Basin

A lot of valuable materials and data were achieved during the 5.12 Wenchuan earthquake,which made the region of Chengdu Basin become more and more interested by researchers.In order to provide the basic materials of equivalent shear wave velocity and overburden of this region for further researches,a multi-channel analysis of surface wave method is applied to the region(E:103°～105°,N:30°～32°) in this paper to get the equivalent shear wave velocity structure and overburden of the basin.40 survey points are evenly distributed in the region with the point space about 20 km.The equivalent shear wave velocity(VS20) and overburden of the basin are obtained.The results show that the distribution character of equivalent shear wave velocity and overburden are similar to the feature of tectonic structure of the basin.At the center of the basin,the equivalent shear wave velocity is mainly in 235 m/s to 330 m/s.While to the northwest side of the basin,the shear wave velocity increases to the range of 330 m/s to 440 m/s.The thickness of the overburden has the same character consistent with the equivalent shear wave velocity.The overburden is thicker at the center of the basin in the range of 8 m to 32 m.While to the northwest side of the basin,the thickness of the overburden decreases to the range of 7 m to 12 m.