摘要
张家口—渤海地震带(简称张渤地震带)与山西地震带交汇区域(113°E～117°E,39°N～42°N)是华北地区北部三个构造单元华北沉降、燕山隆起和太行山隆起的交界处.本文采用张渤带西端的流动地震台网和华北地区北部的区域数字地震台网的地震波形数据,使用SAM方法对该区域地壳介质剪切波分裂参数进行研究.结果表明,北部的燕山隆起地区的快剪切波偏振方向为近EW向,这与华北地区北部的区域应力场方向基本一致.南部的太行山隆起地区,快剪切波偏振方向为NE—NNE,可能与太行山隆起的断裂带走向有关,与山西地震带北部NNE—NE向的断层走向一致.位于研究区域中部的隆起与沉降边界区,快剪切波偏振方向则表现的比较复杂,可能是复杂的局部地质构造引起的.
The cross zone between the Zhangjiakou-Bohai seismic belt and Shanxi seismic belt is the junction of three tectonic elements in the north of Huabei, that is, Huabei subsidence, Yanshan uplift, and Taihang uplift. Using seismic records from temporary seismic stations in the west of Zhangjiakou-Bohai seismic belt and regional seismic stations in Huabei, this paper analyzes the parameters of anisotropic characteristics by the systemic analysis method of shear-waves splitting. The results demonstrate that the polarization directions of fast shear-waves are nearly EW in the north of the studied zone of Yanshan uplift; and are consistent with the direction of the regional principal compressive stress. The polarization directions of fast shearwaves are NE to NNE in the south of the studied zone of Taihang uplift, and are likely related with the strike of the faults, consistent with the fault strike in the north of Shanxi seismic belt. The polarization directions of fast shear-waves in the middle of studied zone are more complicated where is at the boundary between the uplift and the subsidence. This feature probably is caused by the complex geologic structure.
出处
《地球物理学报》
SCIE
EI
CAS
CSCD
北大核心
2011年第6期1517-1527,共11页
Chinese Journal of Geophysics
基金
地震行业科研专项(200708008)
中国地震局地震预测研究所基本科研专项(2007-13))
国家自然科学基金(40674021)资助
关键词
张渤地震带
山西地震带
剪切波分裂
快剪切波偏振方向
应力
地壳
构造
Zhangjiako-Bohai seismic belt, Shanxi seismic belt,Shear wave splitting,Polarization of fast shear-waves, Stress, Crust, Tectonic
