Analysis of spatiotemporal characteristics of surface deformation in Haizhou Open-Pit Mine based on LT-1 SAR satellite

To understand the spatiotemporal distribution patterns of surface deformation in the Haizhou Open-Pit Mine, China's first L-band differential interferometric SAR satellite constellation, LuTan-1 (LT-1), was utilized.A total of 39 ascending and descending LT-1 SAR images from May 2023 to January 2025 were collected.Techniques including D-InSAR and PSInSAR were employed to analyze the spatiotemporal characteristics of surface deformation in the mining area, with optical remote sensing images used to validate the reliability of the results.The findings reveal that the southern slope of the Haizhou Open-Pit Mine exhibits the most significant subsidence, while unstable areas also exist on the eastern and western slopes as well as the central region, though with lesser deformation magnitudes compared to the southern slope.The mining area covers approximately 6.300 km², of which the region with a deformation rate exceeding 0.50 m/a accounts for an area of 0.146 km², representing about 2.3% of the total area.The area with deformation ranging between 0.20 m/a and 0.50 m/a is 0.648 km², constituting approximately 10.3% of the total area.The spatial extent of deformation detected by LT-1 SAR data is generally consistent between ascending and descending orbits, though notable differences exist in the magnitude of deformation rates, with the ascending orbit generally exhibiting lower deformation rates compared to the descending orbit, indicating its lower sensitivity.The descending orbit data provide better observational angles forthe southern and eastern slopes, while the ascending orbit data are more suitable for the western slope.By integrating data from both ascending and descending orbits, the spatial distribution and temporal evolution of deformation in the mining area can be comprehensively reconstructed.