Landform modifications in a glaciotectonic landscape as the result of complex mining activity: Case of the Muskau Arch Geopark, Poland

^{Mining activities lead to significant transformations of the original terrain, resulting in development of new post-mining landscape.} The objective of this study was to assess the land transformations in the result of prolonged, underground and open-pit mining of shallow brown coal deposits in glaciotectonic structure of Muskau-Arch on the Polish-German border in the context of the geoheritage of this area. With this purpose, a geodatabase of thematic datasets representing progress of mining was developed in a geographic information system (GIS) based on topographical maps, mining plans, photographs, and digital elevation models (DEMs). The following timescales: 1903, 1911, 1937, 1955, 1972 and present-day were digitally reconstructed and quantitatively analysed using spatial processing functions including feature layer overlay and DEM differencing. The original, transitional and present-day landscapes were compared and visualised on five thematic maps and tables describing the spatio-temporal transformation of the natural landscape caused by underground and open-pit mining. Approximately 36.85% of the study area has been transformed, giving rise to the landscape of the present-day Geopark. The results provide insight into the genesis of its geoheritage. The adopted methodology, based on the historical GIS (HGIS) approach, can be applied to other post-mining sites, providing relevant documentation is available.