The Precursory 3D Displacement Patterns and Their Implicit Collapse Mechanism of the Ice-Rock Avalanche Events Occurred in Sedongpu Basin Revealed by Optical and SAR Observations

• DOI: 10.3390/rs15112818
• Publication Date: 2023-05-29T11:49:23Z
• Authors: Chao Ding; Guangcai Feng; Lu Zhang; Qiang Shen; Zhiqiang Xiong; Mingsheng Liao
• Keywords: optical and SAR observations; Sedongpu Basin; Science; Q; 04 agricultural and veterinary sciences; 15. Life on land; ice-rock avalanche; Sedongpu Basin; optical and SAR observations; precursory 3D displacement patterns; collapse mechanism; precursory 3D displacement patterns; collapse mechanism; 13. Climate action; ice-rock avalanche; 0401 agriculture, forestry, and fisheries

Quantifying the kinematic evolution patterns of mountain glaciers near Yarlung Tsanpo River performs a major role in evaluating glacial instability and secondary disasters. For Sedongpu Basin Valley, dramatic geomorphic landscape variations triggered by ice-rock avalanche events were visually identified as dominant texture deficiencies time-series optical images. To improve image correlation quality broken these deficiencies, Landsat-8/Sentinel-2 images divided into different groups, then stepwise combination strategy was innovatively proposed to derive glacier displacement velocities temporal stages. The standard deviations (STD) measurements stable area maintained around 0.04 m/yr for normalized velocity from 0.6 1.7 m cumulative time series. obvious before each collapse event. Subsequently, offset-tracking procedures performed on 7 Sentinel-1A Synthetic Aperture Radar (SAR) acquire range azimuth velocities. better reveal dynamic mechanism activity, three-dimensional (3D) also derived using SAR results. precipitation, temperature, seismic activities assumed main triggering factors controlling final events. Additionally, active conformed power law, which limited changes internal stress friction force sliding base surface. aim this study is shed light interpreting precursory their implicit failure with conventional freely observations.