摘要
根据乌海地区构造环境,采用SAM方法研究乌海地区地壳各向异性特征,使用乌海地震台2014年1月至2020年6月数字地震波形进行分析。根据65个有效地震记录,得到乌海地区剪切波分裂参数,其中快剪切波平均优势偏振方向为NE63.1°±46.4°,慢剪切波平均时间延迟为(1.13±0.66)ms/km。乌海地震台快剪切波偏振显示出4个优势偏振方向,分别为NE、EW、NNE、NNW向。将得到的各向异性结果与研究区应力场和地质构造进行分析,认为研究区周边复杂的剪切波分裂变化是主压应力场、原地主压应力、断裂带分布共同作用的结果。
According to the tectonic environment of Wuhai area,this study uses the SAM method to study the crustal anisotropy characteristics of Wuhai area,and uses the digital seismic waveforms of Wuhai Seismic Station from January 2014 to June 2020 for analysis.According to the 65 data obtained According to the results of effective seismic records,the shear wave splitting parameters of Wuhai area are initially obtained.The average polarization direction of fast shear waves is NE63.1°±46.4°,and the average time delay of slow shear waves is(1.13±0.66)ms/km.The polarization of fast shear waves at Wuhai Station shows four dominant directions,one is NE direction,one is EW direction,one is NNE direction,and the other is NNW direction.Analyzing the obtained anisotropy results with the stress field and geological structure of the study area,it is believed that the complex changes in shear wave splitting around the study area are the result of the combined action of the principal compressive stress field,the in-situ principal compressive stress,and the distribution of fractures.
作者
魏建民
张晖
赵星
张浩鸣
郝亮
阿那尔
Wei Jianmin;Zhang Hui;Zhao Xing;Zhang Haoming;Hao Liang;A Naer(Seismological Bureau of Inner Mogolia Autonomous Region,Hohhot 010010,China)
出处
《震灾防御技术》
CSCD
北大核心
2020年第4期777-787,共11页
Technology for Earthquake Disaster Prevention
基金
内蒙古自治区地震局局长基金(2019ZF12、2020JP01)。
