Multi-source Remote Sensing Dynamic Deformation Monitoring of Accumulation Landslide
Objectives:The response law of ancient(old)landslides in the reservoir area is an important re-search topic.Previous research primarily analyzed real-time surface displacement and reservoir water level data.However,professional monitoring conditions are often lacking on most reservoir bank slopes.This complicates tracking the landslide's historical deformation.Satellite and airborne remote sensing platforms enable multi-scale,long-term monitoring of landslide deformation and damage.Methods:This study em-ploys multi-source three-dimensional observation technologies including aerial,space-based,and terrestrial platforms to monitor the deformation and evolution of the Pubugou Hydropower Station's Hongyanzi land-slide over approximately 10 years.It utilizes unmanned aerial vehicle photography(optical imaging)and light detection and ranging(LiDAR)for detailed topographic mapping and deformation analysis from 2009 to 2020.Additionally,time-series interferometric synthetic aperture radar(InSAR)technology is used to track long-term surface deformations from October 2014 to July 2020.Field investigations have identified typical deformation and failure characteristics of the landslide,incorporating geological conditions and exter-nal factors such as rainfall and reservoir water levels to analyze causal mechanisms and dynamic trends.Re-sults:The irregularly semicircular Hongyanzi landslide spans 20-50 m in thickness,encompasses approxi-mately 15.53 million m3 in volume,and slides at an approximate bearing of 340°.Composed of quaternary pebbled stones,silty sand,and clay,the landslide's bed slopes between 20° and 25°.Its lithology includes Emeishan Formation basalt and Yangxin Formation dolomite.Existing since 2006 or earlier,the landslide features elements like walls and steps.LiDAR imagery from 2009 clearly delineates its boundaries,though it shows no new signs of deformation or failure.Following reservoir impoundment,the reactivated land-slide develops new,widening cracks along its rear edge.Post-reactivation,the landslide predominantly un-dergos uniform deformation,with more significant movement at the trailing edge than the leading edge,without marked acceleration.Heavy rainfall is the most significant control factor,imparting stepwise defor-mation characteristics to the landslide.Conclusions:A comprehensive analysis of multi-source data reveals that phenomena like the Hongyanzi landslide exhibit typical long-term,gradual,and seasonal movements.Long-term InSAR effectively captures these characteristics.Multi-stage optical remote sensing and surface point cloud data from LiDAR,after vegetation removal,enable more intuitive comparisons of macroscopic deformation across different landslide areas.Integrating this with geological assessments and field investiga-tions allows for detailed engineering analyses to ascertain the causes,patterns,and future trends of land-slide activity.
万方数据
维普
