The investigation of the Akchour landslide(AKL)demands precise examination on a local scale,which necessitates field surveys that are often hindered by the landslide's steep and extensive nature of the landslide(1...The investigation of the Akchour landslide(AKL)demands precise examination on a local scale,which necessitates field surveys that are often hindered by the landslide's steep and extensive nature of the landslide(1100 m×400 m,ΔZ of 300 m).Digital Elevation Models(DEMs)are among the key datasets used to achieve this objective.A comparative study between freely available DEMs such as Shuttel Radar Topography Mission(SRTM)(30 m×30 m)and Phased Array type L-band Synthetic Aperture Radar(PALSAR)(12.5 m×12.5 m),alongside those generated by unmanned aerial vehicles(UAVs)demonstrates their significant potential for both geomorphological and geomorphometric analysis.Indeed,scaling issues can lead to the oversight of crucial geological elements.Aerial photos at a 1/20000 scale,previously utilized for anaglyph,provide a broad overview but lack detailed information.To address this limitation,we employed the UAV to capture high-resolution aerial views(with a ground resolution of 17 cm).This approach enabled exploration of inaccessible areas,photogrammetry for orthophotos,and the generation of precise DEM supported geomorphological studies.The orthophoto allowed for detailed visual assessment,while the DEM facilitated geomorphological study.The dynamic behaviors within the landslide.Furthermore,the former irrigation network likely exacerbates the situation.Fractures delineating an unstable area are prominent along the main scarp suggesting the possibility of further sliding.This UAV-mapping revealed three distinct zones with varying based approach significantly enhances our understanding of the AKL,surpassing the limitations of traditional methods and providing critical insights into its morphology and potential risks.展开更多
Empirical functional models for the maximum and minimum detectable deformation gradient of PALSAR interferometry were established based on coherence and discrete look numbers. Then, a least square regression method wa...Empirical functional models for the maximum and minimum detectable deformation gradient of PALSAR interferometry were established based on coherence and discrete look numbers. Then, a least square regression method was used to fit the model coefficients and thus obtain the generalized functional models for both coherence and look numbers. The experimental results with ALOS PALSAR data of Wenchuan earthquake of China show that the new model works well for judging whether the deformation gradient can be detected by the D-InSAR technology or not. The results can help researchers to choose PALSAR data and to configure processing parameters, and also benefit the interpretation of the measured surface deformation.展开更多
文摘The investigation of the Akchour landslide(AKL)demands precise examination on a local scale,which necessitates field surveys that are often hindered by the landslide's steep and extensive nature of the landslide(1100 m×400 m,ΔZ of 300 m).Digital Elevation Models(DEMs)are among the key datasets used to achieve this objective.A comparative study between freely available DEMs such as Shuttel Radar Topography Mission(SRTM)(30 m×30 m)and Phased Array type L-band Synthetic Aperture Radar(PALSAR)(12.5 m×12.5 m),alongside those generated by unmanned aerial vehicles(UAVs)demonstrates their significant potential for both geomorphological and geomorphometric analysis.Indeed,scaling issues can lead to the oversight of crucial geological elements.Aerial photos at a 1/20000 scale,previously utilized for anaglyph,provide a broad overview but lack detailed information.To address this limitation,we employed the UAV to capture high-resolution aerial views(with a ground resolution of 17 cm).This approach enabled exploration of inaccessible areas,photogrammetry for orthophotos,and the generation of precise DEM supported geomorphological studies.The orthophoto allowed for detailed visual assessment,while the DEM facilitated geomorphological study.The dynamic behaviors within the landslide.Furthermore,the former irrigation network likely exacerbates the situation.Fractures delineating an unstable area are prominent along the main scarp suggesting the possibility of further sliding.This UAV-mapping revealed three distinct zones with varying based approach significantly enhances our understanding of the AKL,surpassing the limitations of traditional methods and providing critical insights into its morphology and potential risks.
基金Projects(41222227,U1231105)supported by the National Natural Science Foundation of ChinaProject(13JJ1006)supported by the Natural Science Foundation of Hunan Province,China
文摘Empirical functional models for the maximum and minimum detectable deformation gradient of PALSAR interferometry were established based on coherence and discrete look numbers. Then, a least square regression method was used to fit the model coefficients and thus obtain the generalized functional models for both coherence and look numbers. The experimental results with ALOS PALSAR data of Wenchuan earthquake of China show that the new model works well for judging whether the deformation gradient can be detected by the D-InSAR technology or not. The results can help researchers to choose PALSAR data and to configure processing parameters, and also benefit the interpretation of the measured surface deformation.
