摘要
2016年野外地质调查发现渭河盆地东北侧安仁镇发育48条地裂缝,造成沿线房屋墙体开裂、道路错断和农田变形龟裂等,并严重威胁大西高铁安全运营。通过详细的地质调查和地质测绘发现其均位于地貌分界线两侧并发育在双泉-临猗断裂上盘,地裂缝走向为NE60°~80°,按发育位置可将其划分为5组地裂缝。选取典型地裂缝为研究对象,利用槽探和工程地质钻探揭示了地裂缝的剖面结构特征,发现地裂缝导致浅部土体破裂严重,地裂缝错断两侧地层且位错量随深度增加而增加,表现出同沉积断层的性质。在此基础上,对比西安地裂缝并详细分析了安仁镇地裂缝的成因机理,发现构造断裂、地震活动和表水潜蚀是地裂缝形成的主要因素。安仁镇地裂缝成因机理可概化为:构造控缝、地震启缝和表水扩缝。
During the field survey in 2016, 48 earth fissures were discovered in the Anren county, North-East of the Wei River Basin. These fissures have resulted in severe geo-hazards. To determine the characteristics and the formation mechanism of these earth fissures, a series of geological investigation methods, such as field investi gations, measurements, seismic exploration, geological drilling, and trench excavation were employed. Field investigations and measurements indicated that these earth fissures were distributed along the geomorphic boundary and developed on the hanging wall of Shuangquan-Linyi fault. They were found to be trending in 60°~80°direction and were divided into five groups. Searches across the earth fissures revealed that multiple secondary fissures existed on both sides of these earth fissures, indicating that earth fissures caused severe soil ruptures in the shallow earth surfaces. Geological drilling profiles revealed that earth fissures dislocate several stratums and reflected that they possess the characteristics of syn-sedimentary faults. Seismic reflection profiles revealed that buried faults existed under the earth fissures, which showed that earth fissures were outcrops of buried faults. Regarding their genesis, these fissures were formed owing to the coupling action of multiple factors. The earth fissures forming process at Anren area can be divided into three stages. The regional extension first generated multiple buried faults. Then, the seismic activity ruptured multiple strata near the buried faults and formed multiple buried fractures. Finally, erosion process resulting from water infiltration caused the buried fractures to propagate to the surface and promote the formation of current earth fissures.
作者
刘聪
乔建伟
彭建兵
夏玉云
卢全中
周远强
LIU Cong;QIAO Jianwei;PENG Jianbing;XIA Yuyun;LU Quanzhong;ZHOU Yuanqiang(School of Geological Engineering and Geomatics,Chang an University,Xi an 710054,China;Key Laboratory of Western China Mineral Resources and Geological Engineering,Xi an 710054,China;China JK Institute of Engineering and Design,Xi an 710043,China;Shaanxi Key Laboratory for the Property and Treatment of Special Soil and Rock,Xi an 710043,China)
出处
《工程地质学报》
CSCD
北大核心
2022年第1期242-253,共12页
Journal of Engineering Geology
基金
国家自然科学基金项目(资助号:41877250)
自然资源部地面沉降监测与防治重点实验室开放基金(资助号:KLLSMP202001)
中国地质调查局地质调查项目(资助号:DD20160264)
长安大学高校基金(资助号:300102268206,300102260402)
中设集团科技孵化基金(资助号:CMEC-KJFH-2018-02)
陕西省科技统筹创新工程计划项目(资助号:2011KTZB03-02-02)。
关键词
渭河盆地
安仁镇
地裂缝
基本特征
成因机理
Weihe Basin
Anren county
Earth fissure
Basic characteristic
Formation mechanism
作者简介
第一作者:刘聪(1979-),男,博士,讲师,主要从事地质灾害方面的教学与研究工作.E-mail:liucong@chd.edu.cn;通讯作者:彭建兵(1953-),男,博士,教授,博士生导师,主要从事工程地质与灾害地质方面的研究与教学工作.E-mail:dicexy_1@126.com。
