融合InSAR与信息量-层次分析法的深圳西部填海区地面沉降风险评价OACHSSCD

To accurately evaluate the ground subsidence risk in the western reclamation area of Shenzhen,this study proposes a ground subsidence risk evaluation model integrating satellite InSAR observations with the information value-analytic hierarchy process(AHP)method.Firstly,small baseline subset interferometric synthetic aperture radar(SBAS-InSAR)technology was used to obtain ground subsidence data of the study area,and the high-precision deformation observation results are incorporated as the gas key geological disaster factors into the ground subsidence susceptibility evaluation system.Considering the unique subsidence mechanism of soft soil consolidation in reclamation areas,the reclamation age is innovatively introduced into the evaluation index system.Combined with the subsidence characteristics including the spatial differentiation of land use and seasonal precipitation response in the study area,five core evaluation factors,namely reclamation age,InSAR-derived subsidence rate,cumulative subsidence,land use type,and annual average precipitation,are selected to establish a targeted ground subsidence susceptibility model for reclamation areas.Meanwhile,the spatial density of InSAR point is used to characterize regional subsidence vulnerability,and a dual-dimensional"probability-loss"ground subsidence risk evaluation model is constructed by coupling susceptibility and vulnerability indicators.The results show that the area of high and extremely high subsidence risk zones is 0.72 km2,which is characterized by"short reclamation time(<15 years),high subsidence rate(<-20 mm/a),large cumulative subsidence(<-40 mm),and dense building distribution".The extremely low-risk areas are predominately regions with stable ground soil and minor external loads.Comparative verification indicates that the evaluation results of the proposed ground subsidence risk model are highly consistent with the actual subsidence risk.The"probability-loss"dual-dimensional risk evaluation is more scientific and reasonable than the single susceptibility model;incorporating reclamation age into the evaluation index system allows full consideration of the impact of soft soil consolidation degree on subsidence,making it more suitable for the subsiendence development patterns of reclamation areas.The research results can provide technical support for the rapid screening and comprehensive prevention of ground subsidence risk in reclamation areas.