川藏高速巴塘-芒康段地质灾害遥感综合早期识别研究

Remote Sensing Integrated Identification of Geological Hazards in the Batang—Mangkang Section of the Sichuan—Tibet Highway

G4218高速公路所处的巴塘—芒康段位于金沙江河谷至高原的过渡带,新构造活动强烈,岩体破碎,地质灾害问题频发,该地区高速公路的修建和维护面临着巨大的挑战。传统地面地质调查手段在公路选线和地灾评价分析及稳定性评价等多方面面临诸多困难,利用光学遥感对地质灾害点解译,并与InSAR变形观测技术相结合,有望能高效、准确地调查区域内地质灾害点,并揭示其发育和分布规律。在青藏高原高山峡谷区特殊的地质条件下,总结了该区域常见的地质灾害类型,针对研究地区灾害类型特点,结合遥感技术提出公路遥感综合识别技术方法。利用该方法对巴塘—芒康段进行灾害调查,在充分掌握了光学遥感目视解译技术与InSAR技术的情况下,辅以野外地质调查、GIS空间分析、工程地质类比等工作,得到如下结论:1)研究区内光学目视遥感解译出固有地质灾害670处,结合4种SAR数据的InSAR技术解译出活动地质灾害数量220处;2)研究区不同类型地质灾害的发育规律随着地形地貌、地质条件和地质灾害等影响因子的变化存在较大差异,光学遥感解译和InSAR解译出的地质灾害在空间分布上和地层岩性上均存在一定差别;3)根据野外工作对比分析,判断光学遥感解译结果和In-SAR解译结果与二者的解译方式、影像的成像条件及滑坡的活动性存在一定的关系,二者不能直接进行检验互查;4)综合遥感技术方法的使用在青藏高原高山峡谷区的公路建设中具有普适性,其充分利用了光学遥感解译技术和InSAR变形观测技术的互补性,在节约时间成本的基础上,对区域的地质灾害发展情况有了更加全面、准确的了解。

The Batang—Mangkang section of the G4218 highway is located in the transition zone from the Jinsha River Valley to the plateau,and facing with strong neotectonic activities,broken rock masses and frequent geological disasters.Therefore,the construction and maintenance of the highway in this region are of huge difficulties.Traditional ground geological survey methods face many difficulties in highway route selection,disaster assessment and stability analysis,etc.Combining the optical remote sensing interpretation of geological hazard points with deformation observation by InSAR technology,it is expected that the geological hazard points in this region can be investigated quickly,accurately and efficiently,and reveal their development and distribution rules of geological disaster points.Under the special geological conditions of the high mountains and valleys of the Qinghai–Tibet Plateau,the common types of geological disasters in the region were summarized,and the method of integrated highway remote sensing identification was put forward based on the study of the characteristics of regional disasters and remote sensing technology.Using this method,we carried out disaster surveys on the Batang—Mangkang section,with full knowledge of optical remote sensing visual interpretation technology and InSAR technology,supplemented by field geological survey,GIS spatial analysis,engineering geological analogy,etc.The conclusions of this article are as follows:1)A total of 670 geological disasters were interpreted by optical visual remote sensing in the study area,and InSAR technology combined with four kinds of SAR data interpreted 220 active geological disasters;2)The development rules of different types of geological disasters in the study area varied greatly with the change of topographic features,geological conditions and geological disasters and other influencing factors.There were differences in spatial distribution and formation lithology of geologic hazard using the optical remote sensing or InSAR technology;3)According to the comparative analysis based on the field work,it was concluded that the interpretation results of optical remote sensing and InSAR had a certain relationship with the interpretation methods,imaging conditions of the images and the activity of landslide.The two methods cannot be used for mutual inspection directly;4)The use of comprehensive remote sensing technology was universal in the highway construction of the high mountain valley of the Qinghai–Tibet Plateau.It made full use of the complementarity of optical remote sensing interpretation technology and InSAR deformation observation technology.On the basis of saving time and cost,this method can have a more comprehensive and accurate understanding of the development of regional geological disasters.