Continuous long-term (2016-2021) monitoring of the surface deformations in the Upper Silesian Coal Basin, Poland

Abstract

[EN] The Upper Silesian Coal Basin (USCB), located in Southern Poland, is one of the biggest coal deposits in Europe. It is continuously exploited since 18 century and it is one of the main industrial factors in the regional economy. As a result this is also the second populated region in Poland with 4.5 million inhabitants in the administrative province of Silesia. The extensive extractions of the underground coal resources in USCB trigger significant terrain changes leading to subsidence exceeding 1.5 m per year in some areas. Within the frames of two consecutive phases of the Polish contribution to the European Plate Observing System (EPOS) initiative, namely EPOS-PL and EPOS-PL+, a long-term monitoring over the area of USCB is performed using the advantages of the Differential Synthetic Aperture Radar (DInSAR) technology. C-band radar images acquired by the European Space Agency’s Sentinel-1 mission comprising the period between the years of 2016 and 2021 are processed to delineate the range and amplitude of the deformation zones for chosen test sites. The Sentinel-1 constellation provides imagery with revisit time of 6 days, higher than the classical techniques. The standard approach include measurements like levelling, performed 2 to 6 times per year over chosen lines, or measurements with Global Navigation Satellite System (GNSS), while the DInSAR approach gives wider in space and time coverage. The long period of observations gives the opportunity to assess the surface behavior due to the coal underground extractions and to construct more precisely the model of deformations.