摘要
安塞区主城区范围内的基岩地层发育一以延河为枢纽线、走向约330°的背斜构造,在基岩地层中普遍发育走向与褶皱轴面平行(320°~340°)和垂直(40°~60°)两个方位的两组张性节理,还发育有两组与褶皱轴斜交的共轭剪切节理,第一组共轭剪切节理面走向为近南北(0°~10°)和近东西(80°~90°),第二组共轭剪切节理面走向为100°~120°和200°~210°。上述基岩中发育的、不同走向的多组节理面对研究区内具相同走向分布特征的崩塌结构控制面的发育有较强控制作用。第一组共轭剪节理中走向近东西(80°~90°)的节理面控制着研究区内发育程度最高的崩塌结构控制面,它与区内岩质崩塌的发育相关程度最高;其次是两组张性节理面分别控制着走向相同且发育程度较高的两组岩质崩塌结构控制面,第二组共轭剪节理面则控制着区内发育程度相对较低的、走向与共轭节理面相同的两组崩塌结构控制面。
An anticlinal structure with an axis plane along Yanhe river and a strike of about 330°is developed in the bedrock strata within the main urban area of AnSai County.In the bedrock strata,there are generally two groups of tensile joints parallel to the fold axis plane(320°-340°)and vertical(40°-60°),and two groups of conjugate shear joints diagonally intersecting the fold axis.The first group of conjugate shear joint planes struck direction near N-S(0°-10°)and near E-W(80°-90°),while the second group of conjugate shear joint planes strikes direction 100°-120°and 200°-210°.The multiple groups of joints with different strike directions developed in the bedrock have a strong control effect on the development of the collapse structure control plane with the same strike distribution in the study area.In the first group of conjugate shear joints,the near E-W(80°-90°)distributed joint planes control strongly the most developed collapse structure control planes in the study area,and it has the highest correlation with the development of rock collapse in the study area.Secondly,two groups of tensile joint planes control two groups of highly developed rock collapse structural control planes with the same strike,and the second group of conjugate shear joint planes controls two groups of relatively less developed rock collapse structural control planes with the same strike.
作者
王虎
郭怀军
王益民
薛强
王凯
查显锋
王晓勇
孙萍萍
程秀娟
WANG Hu;GUO Huaijun;WANG Yimin;XUE Qiang;WANG Kai;ZHA Xianfeng;WANG Xiaoyong;SUN Pingping;CHENG Xiujuan(Xi’an Center of China Geological Survey,Xi’an,Shaanxi 710054,China;Key Laboratory for Geo-hazards in Loess Area,MLR,Xi’an,Shaanxi 710054,China)
出处
《中国地质灾害与防治学报》
CSCD
2022年第3期51-60,共10页
The Chinese Journal of Geological Hazard and Control
基金
中国地质调查局地质调查项目(DD20189270,DD20211398)。
关键词
地质灾害
岩质崩塌
结构控制面
基岩节理
黄土高原
geological disaster
rock collapse
structural control planes
bedrock joints
Loess Plateau
