Reservoir landslides are significant geological hazards that pose severe risks to reservoir safety.Detecting the spatial-temporal evolution of slope movement is crucial for effective risk assessment and disaster mitig...Reservoir landslides are significant geological hazards that pose severe risks to reservoir safety.Detecting the spatial-temporal evolution of slope movement is crucial for effective risk assessment and disaster mitigation.InSAR technology has been extensively employed to monitor surface deformations in reservoir landslides.However,the accuracy of InSAR-derived deformation fields is often limited by the reliability of prior deformation model.Traditional models,which primarily rely on linear or periodic function,frequently overlook the step-like evolution characteristics of reservoir landslides.To address this limitation,this study introduces a multi-temporal InSAR approach that incorporates Sigmoid function to enhance the deformation modeling of reservoir landslides.To solve the nonlinear parameters within the model,Taylor series expansion-based observation equation is constructed to estimate these parameters accurately.The proposed model was evaluated using both the simulated and real datasets from the Hongyanzi landslide in the Pubugou reservoir area.The results demonstrate that the proposed model significantly improves the accuracies of parameter estimation and deformation time-series.Experiments conducted under the sensitivity of interferogram stacks and varying atmospheric phase screen interference magnitudes further confirm the proposed model’s robustness and application potential.In addition,the sensitivity analysis of the initial parameters in the real data experiment scenario demonstrates the robustness of the proposed model’s nonlinear parameter estimation.Finally,the cross-correlation analysis reveals that the deformation of the Hongyanzi landslide is triggered by the decline of the reservoir water level,and quantitatively evaluates the lag time between the deformation and the reservoir water level.Our results offer novel insights for InSAR monitoring of other complex deformation evolution scenarios.Prior information is incorporated into the deformation modeling to estimate a more reliable InSAR deformation field.展开更多
Three-dimensional(3 D) co-seismic surface deformations are of great importance to interpret the characteristics of coseismic deformations and to understand the geometries and dynamics of seismogenic faults. In this pa...Three-dimensional(3 D) co-seismic surface deformations are of great importance to interpret the characteristics of coseismic deformations and to understand the geometries and dynamics of seismogenic faults. In this paper, we propose a method for mapping 3 D co-seismic deformations based on InSAR observations and crustal strain characteristics. In addition, the search strategy of correlation points is optimized by adaptive correlation distance, which greatly improves the applicability of the proposed method in restoring deformations in decorrelation areas. Results of the simulation experiment reveal that the proposed method is superior to conventional methods in both the accuracy and completeness. The proposed method is then applied to map the 3 D co-seismic surface deformations associated with the 2015 MW7.2 Murghab earthquake using ascending and descending ALOS-2 PALSAR-2 images. The results show that the seismogenic fault is the Sarez-Karakul fault(SKF), which is dominated by NE-SW strike slips with an almost vertical dip angle. The north section and the south segment near the epicentre have obvious subsidence along with a southwestward motion in the northwest wall, and the southeast wall has northeast movement and surface uplift trend along the fault zone. The strain field of the earthquake is also obtained by the proposed method. It is found that the crustal block of the seismic area is obviously affected by dilatation and shear forces, which is in good agreement with the movement character of the sinistral slip.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.42474054,42030112)the National Key Research and Development Program Project(Grant No.2021YFC3000500)+3 种基金the Science and Technology Innovation Program of Hunan Province(Grant No.2023SK2012)the Nature Science Foundation of Hunan Province(Grant No.2024JJ6411)the Research Foundation of Education Bureau of Hunan Province(Grant No.23C0295)the Nature Science Foundation of Shaoyang City(Grant No.2024PT6099).
文摘Reservoir landslides are significant geological hazards that pose severe risks to reservoir safety.Detecting the spatial-temporal evolution of slope movement is crucial for effective risk assessment and disaster mitigation.InSAR technology has been extensively employed to monitor surface deformations in reservoir landslides.However,the accuracy of InSAR-derived deformation fields is often limited by the reliability of prior deformation model.Traditional models,which primarily rely on linear or periodic function,frequently overlook the step-like evolution characteristics of reservoir landslides.To address this limitation,this study introduces a multi-temporal InSAR approach that incorporates Sigmoid function to enhance the deformation modeling of reservoir landslides.To solve the nonlinear parameters within the model,Taylor series expansion-based observation equation is constructed to estimate these parameters accurately.The proposed model was evaluated using both the simulated and real datasets from the Hongyanzi landslide in the Pubugou reservoir area.The results demonstrate that the proposed model significantly improves the accuracies of parameter estimation and deformation time-series.Experiments conducted under the sensitivity of interferogram stacks and varying atmospheric phase screen interference magnitudes further confirm the proposed model’s robustness and application potential.In addition,the sensitivity analysis of the initial parameters in the real data experiment scenario demonstrates the robustness of the proposed model’s nonlinear parameter estimation.Finally,the cross-correlation analysis reveals that the deformation of the Hongyanzi landslide is triggered by the decline of the reservoir water level,and quantitatively evaluates the lag time between the deformation and the reservoir water level.Our results offer novel insights for InSAR monitoring of other complex deformation evolution scenarios.Prior information is incorporated into the deformation modeling to estimate a more reliable InSAR deformation field.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41404011, 41674010 & 41704001)the Key Research and Development Plan of Hunan Province, China (Grant Nos. 2016SK2002 & 2017RS3001)+2 种基金the Innovation Platform Public Foundation of the Education Department of Hunan Province, China (Grant No. 16K053)the Land and Resource Department Scientific Research Program of Hunan Province, China (Grant No. 2017-13)the Special Funds for Basic Scientific Research Services of Central Higher Education Institutions of Central South University (Grant No. 2017ZZTS772)
文摘Three-dimensional(3 D) co-seismic surface deformations are of great importance to interpret the characteristics of coseismic deformations and to understand the geometries and dynamics of seismogenic faults. In this paper, we propose a method for mapping 3 D co-seismic deformations based on InSAR observations and crustal strain characteristics. In addition, the search strategy of correlation points is optimized by adaptive correlation distance, which greatly improves the applicability of the proposed method in restoring deformations in decorrelation areas. Results of the simulation experiment reveal that the proposed method is superior to conventional methods in both the accuracy and completeness. The proposed method is then applied to map the 3 D co-seismic surface deformations associated with the 2015 MW7.2 Murghab earthquake using ascending and descending ALOS-2 PALSAR-2 images. The results show that the seismogenic fault is the Sarez-Karakul fault(SKF), which is dominated by NE-SW strike slips with an almost vertical dip angle. The north section and the south segment near the epicentre have obvious subsidence along with a southwestward motion in the northwest wall, and the southeast wall has northeast movement and surface uplift trend along the fault zone. The strain field of the earthquake is also obtained by the proposed method. It is found that the crustal block of the seismic area is obviously affected by dilatation and shear forces, which is in good agreement with the movement character of the sinistral slip.
