Time-Series Deformation Monitoring over the Kalush-Golynsk Potassium Salt Deposit (Ukraine), Using InSAR Method

Abstract

Improper liquidation of underground mine cavities can lead to the development of hazardous geodynamic processes, including progressive surface subsidence and ground instability in mining regions. This study demonstrates a workflow for satellite radar monitoring of deformation processes in mining regions using Sentinel-1 SAR data. Time-series analysis was performed using the NSBAS (New Small Baseline Subset) method implemented in the MintPy software package. Interferogram generation was automated through the HyP3 cloud processing platform of the Alaska Satellite Facility, while subsequent analysis was conducted in the Jupyter Notebook environment provided by the OpenSARlab platform. A total of 295 interferometric pairs covering the period from April 2021, to March 2024 were analyzed. Tropospheric delay corrections were introduced using ERA5 atmospheric reanalysis data distributed via the Climate Data Store service. The resulting mean velocity map reveals several zones of intensive subsidence within the Novo-Holyn mining field, including the area of a large sinkhole currently flooded with water, the roof of a reclaimed tailings storage facility, and parts of the nearby residential area. In some locations, deformation rates approach 50 cm/year, indicating rapid surface destabilization related to underground mining processes. To validate the InSAR results, four annual campaigns of high-precision second-order levelling were conducted. A comparison of deformation rates along four levelling profiles shows good agreement between satellite radar monitoring and ground-based geodetic measurements. The presented approach demonstrates that time-series InSAR analysis with short temporal baselines can provide reliable deformation estimates even under conditions of rapid subsidence and strong temporal decorrelation typical of mining areas. The proposed processing workflow can therefore be applied to other regions affected by underground mining or similar geodynamic processes, expanding the practical capabilities of satellite radar monitoring for early detection and localization of hazardous surface deformation.