Identification of landslide hazards in western Hubei mountainous area by combining PS-InSAR and SBAS-InSAR——Taking Qingjiang River Basin of Changyang County as an example
Identification of landslide hazards in western Hubei mountainous area by combining PS-InSAR and SBAS-InSAR——Taking Qingjiang River Basin of Changyang County as an example
In view of the frequent occurrence of landslides and other disasters in the mountainous areas of West Hubei,and the difficulty of investigation in some areas due to the steep terrain and the uncertainty of the spatial distribution and future development trend of potential landslide hazardous areas,how to make use of surface deformation data obtained by InSAR technology to realise the early identification of landslide hazardous areas has become a popular direction of landslide research.Using the Sentinel-1A up-orbit data,we obtained the surface deformation information of the north bank of Qingjiang River Basin in Changyang County from July 2020 to December 2021 based on PS-InSAR and SBAS-InSAR techniques,respectively,and then superimposed and fused the surface deformation information obtained by the two methods to iden-tify the possible landslide hazard areas in the study area by taking into consideration of the geological back-ground conditions of the study area,the historical landslide sites,and the thickness of the quaternary over-burden.The potential landslide hazard areas in the study area were identified by considering the geological background conditions,historical landslides and the thickness of the Quaternary overburden,and the relia-bility of the identification results was analysed by combining the GNSS monitoring data.The results are as follows:the surface deformation rate in the study area obtained based on PS-InSAR and SBAS-InSAR tech-niques are from-32.03 to 16.74 mm/a and from-53.33 to 26.94 mm/a,respectively,and based on the natural breakpoint method to jointly analyse the monitoring results obtained by the two methods,the sur-face deformation rate in the study area is finally divided into 5 five grades,and the study area is identified as having 18 potential landslide hazards with a total area of 27.58 km2,mainly distributed in the western part of the study area from Zhaolai River to Ziqiu Town along Qingjiang River.The fusion of the interpretation results of the two InSAR techniques,PS and SBAS,can not only further improve the accuracy of the identi-fication of landslide hazardous areas and provide a more reliable scientific basis for the prevention and con-trol of regional geologic hazards,but also provide a new idea for the identification of landslide hazardous ar-eas based on the InSAR technique.It also provides a new idea for the identification of landslide hazardous areas based on InSAR technology.
关键词
滑坡隐患/早期识别/地表形变监测/PS-InSAR/SBAS-InSAR/长阳县清江流域
Key words
potential landslide hazard/early identification/surface deformation monitoring/PS-InSAR/SBAS-InSAR/Qingjiang River Basin of Changyang County
万方数据