摘要
构造、侵蚀与人为等多种因素均影响着冲洪积扇线性陡坎的形成和发现。结合无人机高分辨率遥感影像解译、地形地貌剖面分析、探槽开挖、工程地质剖面分析和音频大地电磁探测等多种方法,对河西走廊西洞西滩冲洪积扇发育的线性陡坎地貌由浅及深开展综合对比分析,得到如下结论:地形地貌剖面显示线性陡坎两侧地形高程递变平缓,未见变形现象;探槽揭示了线性陡坎两侧下伏的地层连续,底部地层近水平产出且产状明显小于顶部地层,未见地层错断现象;工程地质剖面表明线性陡坎两侧的Q3冲洪积砂卵砾石层顶面连续,未见地层错动现象;音频大地电磁探测结果显示线性陡坎两侧下伏基岩界面连续完整,未见断层通过迹象。因此,综合认为河西走廊西洞西滩冲洪积扇发育的线性陡坎地貌是由大磁窑河水侧向侵蚀作用形成的,而非构造作用所致。
The formation and discovery of linear scarps in alluvial-proluvial fan are affected by many factors,such as structure,erosion and human activities.In this paper,combined with the UAV high resolution remote sensing image interpretation,the topographic and the geomorphological profile analysis,the trench excavation,the engineering geological profile analysis and the audio magnetotelluric detection etc.,we analyzed comprehensively the landform of the linear scarp developed in the alluvial-proluvial fan of the west bank of Xidong in Hexi Corridor from the shallow layer to the deep layer.The conclusions are as follows:the topographic and geomorphological profile indicates that the terrain elevation on both sides of the linear scarp is turning gradually flat without deformation;The trench reveals that the underlying strata on both sides of the linear scarp are continuous,and the bottom strata are nearly horizontal with the occurrence being significantly less than the top strata and there is no stratigraphic fault;The engineering geological section shows that the top surface of Q3 alluvial-proluvial sandy gravel layer on both sides of the linear scarp is continuous,and there is no formation dislocation;The audio magnetotelluric detection results show that the underlying bedrock interface on both sides of the linear scarp is continuous and complete,with no sign of fault passing.Therefore,it is concluded that the linear scarp landform developed in the alluvial-proluvial fan of the west bank of Xidong in Hexi Corridor is formed by not the tectonic effect rather than the lateral erosion of the Daciyao river.
作者
郑荣荧
陈柏旭
周文杰
杨晨爽
Zheng Rongying;Chen Baixu;Zhou Wenjie;Yang Chenshuang(Beijing Disaster Prevention Technology Co.,Ltd.,Beijing 101100,China;Institute of Disaster Prevention,Hebei Sanhe 065201,China;Jiangsu Earthquake Agency,Jiangsu Nanjing 210014,China;Lanzhou Institute of Seismology,China Earthquake Administration,Gansu Lanzhou 730000,China)
出处
《地震科学进展》
2023年第5期203-213,共11页
Progress in Earthquake Sciences
基金
北京防灾科技有限公司研发专项(FZKJYF202201)
国家重大科学计划“第二次青藏高原综合科学考察”(2019QZKK0901)联合资助
关键词
线性陡坎
遥感解译
地形地貌剖面
探槽
工程地质剖面
大地电磁
linear scarp
remote sensing interpretation
topographic and geomorphological profile
trench
engineering geological profile
magnetotelluric
