Karst landslides detection and monitoring with multiple SAR data and multi-dimensional SBAS technique in Shuicheng, Guizhou, China

Abstract

Shuicheng District is a karst mountain area, located in Guizhou Province, China. Its fragile stratum and frequent underground mining activities makes it prone to landslides. Owning to its wide coverage and frequent revisit, the InSAR technology has advantages in potential landslide identification and deformation monitor. However, affected by dense vegetation and atmospheric delay, it is much difficult to get sufficient effective targets to derive the deformation in this area. Besides, deformation derived from single orbit SAR data can result in the missing identification of some potential landslides and the misinterpreting of the real kinematics process of landslides. In this study, the multi-source SAR data, atmospheric error correction by quadratic tree image segmentation method, and phase-stacking method were selected to derive the surface deformation of this area. Besides, DS-InSAR and MSBAS method were combined to derive the deformation of Pingdi landslide. First, the potential landslides in this area were identified, surface deformation result, optical remote sensing images and geomorphological features were jointly considered. Then, the landslide distribution characteristics was analyzed in terms of slope, elevation and stratum. After that, the deformation along the LOS direction was acquired using the DS-InSAR method. The MSBAS method was used to retrieve the two-dimensional deformation of Pingdi landslide. Finally, the comprehensive analysis of triggering factors and failure process were conducted according to the spatial-temporal deformation characteristics and field investigation. The results indicated that landslides in Shuicheng district were mostly located in the junction of T1 and P3 stratum and mining related. Mining activity was the main cause of the Pingdi landslide deformation, the precipitation was the driving factor of the landslide instability. The research provides an insight into the explore the unstable slope distribution characteristic and the failure process of the landslides.

Study on surface deformation pattern in mine closure area of complex karst mountainous region based on SBAS-InSAR technology

“…Under the influence of precipitation and weathering, the existing cracks had already manifested in the mountainous terrain. As coal mining operations progressed, these initial cracks further widened, and new cracks emerged (Sun et al, 2023). These mountain cracks not only compromised the stability of the terrain but also provided pathways for rainwater infiltration into the rock formations, thereby accelerating the karstification process.…”

“…Karst landscapes are widespread throughout China. Specifically, soluble rocks of Karst landscapes cover over an expansive area of up to 365 × 104 km 2 , which accounts for more than one-third of the national territory (Sun et al, 2023). Guizhou Province stands out as the region of Karst landscapes due to its extensive development of carbonate rocks and the thickest exposure, predominantly composed of limestone and dolomite, resulting in the formation of representative karst landforms (Chu et al, 2015).…”