Long-term subsidence over the Upper Silesia Coal Basin identified on differential LIDAR (2012–2021) and InSAR (2015–2020) data

Abstract

We provide a map of subsidence caused by underground mining in Upper Silesia, which hosts the largest coal basin in Poland. The map combines data obtained using two InSAR processing techniques and differential LIDAR data. Persistent Scatterer Interferometry and Differential SAR Interferometry techniques were applied on images from the Sentinel-1 satellite covering a six-year period from 2015 to 2020. As a result, 132 subsidence areas affected by deformation of >5 mm/year covering 430 km² were determined. Additionally, a differential LIDAR model covering the period 2012-2021 was analyzed, where 103 subsidence areas were identified, of a total area of 88 km² and where the largest recorded deformation value exceeded 10 m. Despite the large time difference between the two subsidence datasets, good correlation of the data regarding the location and shape of the troughs was observed. However, comparison of InSAR and LIDAR data showed a large underestimation by DInSAR of values of subsidence in the central parts of the basins. We show the potential of Sentinel-1 and LIDAR data to determine displacements taking place over large areas and over long periods, as a supplement to traditional measurement methods.