中国地质灾害与防治学报2026，Vol.37Issue(3)：96-111,16.DOI:10.16031/j.cghc.202510018
马兰滑坡InSAR三维形变特征与降雨响应机制
InSAR-derived three-dimensional deformation characteristics and rainfall response mechanisms of Malan landslide
摘要
Abstract
Three-dimensional(3D)deformation monitoring of landslides is a key indicator for understanding their kinematic mechanisms and potential hazard risk.Taking the Malan landslide in Tianshui,China,as a case study,this paper employs InSAR-based 3D decomposition combined with rainfall-deformation coupling analysis to reveal the 3D deformation characteristics of the slope and its response to rainfall.Time-series Sentinel-1A ascending and descending SAR images acquired from July 2022 to July 2025 were processed using the SBAS-InSAR method to derive surface deformation series.A slope-aspect-constrained 3D decomposition model was then applied to retrieve deformation rates and cumulative displacements in the vertical,east-west and north-south directions.Based on this,typical profiles and representative points were extracted;the evolution stages of the landslide were characterized using the tangent angle of displacement-time curves,and wavelet coherence analysis with regional rainfall records was conducted to quantitatively assess the influence of rainfall on 3D deformation.(1)The 3D deformation field reveals an asymmetric composite sliding mode dominated by vertical subsidence with superimposed east-west horizontal motion.The maximum cumulative horizontal and vertical displacements reach 52 mm and 14 mm,respectively.The deforming area exhibits stage-wise intensification and marked spatial heterogeneity.(2)Wavelet coherence analysis between 3D point-wise displacement and rainfall indicates that vertical deformation exhibits strong coherence with rainfall at periods of 1-4 months,with coherence coefficients generally greater than 0.8.The phase relationship indicates that rainfall leads deformation by approximately 1-2 months.The east-west component shows scale-dependent coupling with rainfall,whereas the north-south component exhibits relatively weak coherence.Combined analysis of displacement-rainfall time series and tangent-angle evolution further demonstrates that intense summer rainfall events in 2023 and 2024 temporally coincide with multiple acceleration phases of the landslide.Seasonal heavy rainfall is the primary external factor influencing the enhancement of vertical subsidence and east-west sliding of the Malan landslide,which displays distinct stage-wise evolution during the monitoring period.The proposed methodology provides technical support and a methodological reference for refined 3D deformation characterization and early warning of rainfall-affected landslides.关键词
SBAS-InSAR/三维形变反演/降雨型滑坡/小波相干分析/坡向约束法Key words
SBAS-InSAR/three-dimensional deformation inversion/rainfall-induced landslide/wavelet coherence analysis/slope-aspect-constrained decomposition分类
天文与地球科学引用本文复制引用
胡祥祥,樊义佳,石亚亚,安乐平,胡良柏,耿莉伟,段宏伟,张海波..马兰滑坡InSAR三维形变特征与降雨响应机制[J].中国地质灾害与防治学报,2026,37(3):96-111,16.基金项目
国家自然科学基金项目(42361020) （42361020）
甘肃省高校教师创新基金项目(2026A-158) （2026A-158）
