Set-up and application of multisensor-referencestations (MSST) for levelling, GNSS and InSAR in the former mining regions Saarland and Ruhrgebiet within Germany

Abstract

[EN] In 2017 the Mining Authorities Oberbergamt des Saarlands (OBA), the State Office for Survey, Geoinformation and Land Consolidation Saarland (LVGL) of the German federal state Saarland and the former mining company RAG Aktiengesellschaft (RAG) planned and set up a project to realize a modern network of so called multisensor-reference stations (MSST) for the monitoring of ground movements in post-mining and tectonically active regions. The MSST will serve as reference for the combined GNSS, Levelling and InSAR-based “Bodenbewegungskataster Saarland (SaarBoBeKa)”, the ground movement cadaster of LVGL. A MSST consists of a solid heavy double corner reflector (D-CR) suitable for X-, C- and L-Band ascending and descending orbit data, a calibrated permanent registering GNSS chokering antenna and levelling points, all founded in a heavy reinforced concrete block. Additional components are weather-sensors and data transmission units. The MSST will be included into the German SAPOS GNSS framework and height measurements to official levelling points are attached to the German Height Reference System DHHN2016. LVGL operates a network of five MSST, RAG added six MSST distributed over the mining affected area. All LVGL stations are prepared to serve as stations of the German SAPOS GNSS framework and for this have to be supplied by the power network and the data transfer has to be done by LAN or LTE. All of RAG’s MSST are powered by solar-cells and a small wind energy converter. The data transfer is performed by mobile communication to the GLOMON portal of ALLSAT. In GLOMON the RAG measurements are calculated by the program WapNet and sent to LVGL to be integrated in SaarBoBeKa. For the mining district of the Ruhr Area in the federal state of North Rhine-Westphalia (NRW) RAG is currently planning to construct and operate 10 MSST in 2022. The status of the MSST projects are presented.