Taking the Yingpan landslide in the Lancang river basin as the study object, this study employed the SBAS-InSAR technique to process 82 scenes of Sentinel-1 descending orbit images acquired from January 2021 to December 2023 for deformation calculation. The spatiotemporal evolution characteristics of its overall deformation were analyzed. Subsequently, the local deformation features along the road and elevation profiles were thoroughly examined, and the response relationship between time-series deformation and rainfall was investigated. Finally, the fast independent component analysis (FastICA) method was applied to decompose the deformation displacement, revealing the spatial distribution differences and temporal variation characteristics of different deformation components of the Yingpan landslide. The results indicate that during the monitoring period, the maximum deformation rate along the line of sight (LOS) direction reached -65 mm/a, with a maximum cumulative deformation of -175 mm. The deformation area extended over 1 000 m in both east-west and north-south directions, and the deformation characteristics varied across different land cover types. A significant correlation was observed between the magnitude of deformation and rainfall, with deformation being markedly greater during the rainy season than the dry season. FastICA analysis revealed that the overall deformation of the landslide exhibits periodicity.

The reliability of SWOT satellite altimetry-based water level data was validated through extraction and analysis, with the July 2024 flood event in the Dongting lake basin serving as a case study to explore its application potential in dynamic flood monitoring. The results demonstrate that the water level data provided by the SWOT satellite exhibits high accuracy, with an optimal correlation coefficient of 0.99 and a RMSE of 0.55 m when compared to in-situ measurements. The derived water extents also show high spatial consistency with optical imagery.

To improve the interpretation accuracy of aeromagnetic data at different altitudes, this study addresses issues in upward continuation such as the loss of weak signals, excessive suppression of shallow anomalies, and error accumulation from multi-source superposition effects. An integrated compensation method combining height attenuation and local anomaly factors is proposed. Results from theoretical simulations indicate that the error between compensated data and forward-model data is significantly reduced, with the improvement ratio reaching 217.02% at an upward continuation of 5 m (equal to one model height) and still achieving 54.36% at 25 m (five times the model height). For field data, when upward continuing by 10 m from 130 m altitude, the RMSE decreases from 2.955 2 nT to 0.993 2 nT, an improvement of 66.39%. Even at 120 m continuation, the error is further reduced by 2.64%, demonstrating clear enhancement in accuracy. While preserving the structural characteristics of the original data, the compensation method significantly enhances the clarity and spatial resolution of anomaly responses. This provides theoretical support and technical means for refined processing and quantitative interpretation of aeromagnetic data, with promising potential for practical applications.

Taking a certain medical and chemical industrial park as an example, based on the Sentinel-1 satellite data from 2016 to 2024, we analyze the spatiotemporal characteristics of ground deformation in response to environmental governance using SBAS-InSAR technology. The results show that the study area exhibits spatial characteristics of "overall stability with localized subsidence". The maximum cumulative settlement reached 125 mm, primarily attributed to production activities. The factory zones of large enterprises maintained relative stability, and environmental governance project has not had a significant impact on the safety of enterprise buildings and structures. During the environmental governance period, settlement occurred at both ends of the dam, while the settlement in mid-dam conforms to the consolidation characteristics of the earth-rockfill dam, indicating extraction well operation did not have a significant impact on the stability of the dam. The study area has sufficient water resources and timely groundwater recharge, and reasonable extraction well layout and scientific strategy of the environmental governance plan, which have not caused significant disturbance to the regional hydrogeological environment and has limited impact on ground deformation.

Taking Nujiang prefecture as the research object, a M_S7.0 earthquake was set in the southern section of Nujiang fault. Based on the Newmark model and using basic data such as DEM and geological maps, the Arias intensity seismic motion parameter was selected, and the amplification effect of topography on seismic motion was considered to conduct a potential landslide hazard assessment in Nujiang prefecture, obtaining the spatial distribution pattern of potential seismic landslides in the study area. The results show that the areas with high sensitivity to potential seismic landslides in Nujiang prefecture are mainly distributed along the steep slopes on both sides of the Dulong river, Nujiang river, and Lancang river. The areas with low sensitivity are located in the gently undulating intermountain basins. The probability range of landslide instability is 0-11.69%. In the seismic landslide hazard zoning, the areas of extremely low hazard zone, low hazard zone, moderate hazard zone, and high hazard zone account for 78.11%, 12.23%, 5.69%, and 3.39% of the study area, respectively. The moderate and high hazard zones are mainly distributed in the steep slope areas on both sides of the Nujiang fault. In the study area, 23 natural villages and several highways as disaster-bearing bodies are located in the high hazard zone. This research can provide effective reference for seismic landslide emergency assessment, potential seismic landslide hazard prediction, and site selection for engineering construction in Nujiang prefecture.

We integrate multi-source heterogeneous data such as time-series InSAR, LiDAR, engineering geological survey, and drilling to systematically analyze the deformation evolution mechanism of Yingzi landslide in Jinyang county, Liangshan Yi autonomous prefecture, and construct a 3D high-resolution dynamic model that enables real-time forecasting of the hazard process. The results show that: 1) InSAR observations (from 31 Dec 2021 to 15 Dec 2024) reveal that the cumulative displacement of landslide reached -198.01 to 150.51 mm, with the most pronounced deformation localized in zone Ⅰ 1(frontal traction section) and zone Ⅰ 2 (ancient landslide zone). 2) The failure mode follows a compound mechanism of frontal traction-rear compression, which can easily drive shear-plane coalescence and trigger overall instability. 3) Scenario-based simulations indicate that the landslide motion-deposition process lasts about 300 s, with a peak velocity of 55 m/s, and forms a deposit covering 2.96×10⁵ m² with a volume of 5.84×10⁶ m³ and a maximum accumulation thickness of 58.46 m, posing an extremely high risk of river blockage and collapse flooding disaster chain. 4) It is recommended to densify monitoring networks in zones Ⅰ 1 and Ⅰ 2 to capture abrupt deformation, install anti-slide piles and upgrade drainage system at the front edge of zone Ⅰ 1 to inhibit sliding, and initiate relocation of residents in the affected zone. The outcomes provide technical guidance for deformation mechanisms understanding, dynamic modeling, and risk mitigation of high-elevation and long-runout landslides.

We construct daily line-of-sight gravity difference (LGD) series at 5-second intervals using GRACE inter-satellite ranging data and extract LGD anomalies over earthquake regions. Using the 2004 Sumatra M_W9.1 and 2011 Tohoku M_W9.1 earthquakes as case studies, the results confirm that the LGD method can effectively detect coseismic gravity changes within several days after earthquake, and significantly improve temporal resolution. The observed LGD and theoretical LGD peaks show excellent agreement, with absolute differences no more than 0.8 nm/s² (Sumatra earthquake) and 2.5 nm/s² (Tohoku earthquake). This study demonstrates that LGD-based earthquake monitoring offers high speed and accuracy, providing a new technical approach for investigating large-scale mass migration processes caused by seismic events.

Based on GRACE-FO observations from March to April 2022, we analyze the consistency between precise orbit products and KBR/LRI inter-satellite kinematic measurements. The results show that the residuals between KBR/LRI and inter-satellite range, range rate and acceleration derived from the orbit solutions are ±4 mm, ±1×10^-5 m/s and ±1×10^-5 m/s², respectively, with RMS values range from 10^-6 to 10^-3, confirming the reliability of orbit data. In gravity field inversion, the line-of-sight inter-satellite range rate inversion results derived from orbit data exhibit stripe-like noise. The accumulative degree variance of spherical harmonic coefficients is one order of magnitude higher than that of KBR/LRI, and the signal-to-noise ratio is also reduced by about 1. However, in terms of low-degree spherical harmonic coefficients below degree 20, the deviation between this result and CSR reference coefficient is smaller. This phenomenon indicates that orbit data has an advantage in constraining the long-wavelength signals in specific frequency bands for low-degree gravity field model inversion, and can provide valuable supplementary references for multi-source data fusion.

Abstract: Using ascending and descending SAR images from Sentinel-1A satellite, the co-seismic deformation of the M_W5.7 earthquake in Zaduo county, Yushu city on March 7, 2024, was obtained. The geometry parameters and slip distribution of the seismogenic fault were inverted. Finally, based on the Coulomb stress changes induced by the earthquake, the impact on surrounding faults was analyzed and the regional seismic hazard was assessed. The results show that the main deformation areas of the co-seismic deformation fields from both ascending and descending orbits exhibit a four-quadrant distribution, with maximum LOS displacements of approximately 3.1 cm and 3.6 cm for ascending and descending orbits, respectively. Fault inversion experiments indicate that both the northeast-dipping fault model and the northwest-dipping fault model can reasonably explain the surface deformation caused by this earthquake. However, after a comprehensive analysis of co-seismic fitting residuals, regional active fault distribution, and geomorphic features, this study leans towards the conclusion that the seismogenic fault of this earthquake is a northeast-dipping strike-slip fault with a northwest-southeast trend. Co-seismic slip is concentrated at depths of 1.5 to 6.0 km, reaching a peak slip of 1.0 m at a depth of 3.7 km. Additionally, the static Coulomb stress changes reveal that the 2024 Zaduo earthquake has increased the risk of future earthquakes in the Yanshiping fault zone.

We collect the focal mechanisms of M≥3.0 earthquakes in western Yunnan region from 2013 to 2024, use the superimposed stress field method to carry out regional tectonic stress inversion, and investigate the spatiotemporal evolution characteristics of focal mechanism consistency before and after M≥5.0 earthquakes. The results show that the focal mechanism in the study area is mainly slip-type, supplemented by normal fault type. The plunge angles of P-axis and T-axis are small, and the fault plane is mostly high dipping. The stress type in the study area is slip-type. The compressive stress is mainly in the direction of NE to NNE, with a better consistency, while the tension stress is dominant in the direction of SEE. The dip angles of compressive stress and tension stress are small and close to the horizontal in western Yunnan. The study area is mainly characterized by horizontal stress and is subject to horizontal compression in the NE to NNE direction and tension in the SEE direction. The M≥5.0 earthquakes occurred in areas with low variance of stress tensor or their edges, and the stress tensor variance experienced the process of decreasing from the peak before the earthquake. The continuous decrease or low level of stress tensor variance may be closely related to the risk of moderate earthquakes in the western Yunnan, but the relationship between them is not unique, and can be comprehensively analyzed by combining with other parameters, such as the low b-value. The research findings provide a reference for analyzing seismic source characteristics, studying tectonic stress, and tracking seismic activity in the study area.