This dataset is part of a research collaboration between Energie und Wasser Potsdam (EWP) and the GFZ Helmholtz Centre for Geosciences. The main objective of this research collaboration was to evaluate the suitability of the subsurface in the Potsdam area for deep geothermal energy. EWP is currently constructing a geothermal power plant using the aquifer of the here exploited Jurassic sandstones.
From December 2022 to May 2023, two deep wells were drilled in the center of the city Potsdam, Germany, targeting the Jurassic Aalenian Sandstone at depths between 983 and 1180 m below surface. Hydraulic tests were performed immediately after completion of each well. More than 15,000 m3 of formation water was produced. Geochemical analysis were performed on the produced formation water with the objective of characterizing the fluid properties in terms of geothermal usage, e.g. corrosion and scaling potential. The results of the analysis of physicochemical on-site monitoring and performed on-site tests, inorganics, organics, gas composition, heat capacity and naturally occurring radioactive materials are presented in this data publication.
Real-time fluid monitoring began in late 2020 in the East Eifel and currently includes 12 sites, such as abandoned CO₂ wells, mofettes, CO₂-rich springs, CO₂-rich soil, and a cold-water geyser in the West Eifel. For the first time, fluid data are being recorded continuously with a high temporal resolution of up to 1 Hz. Depending on the local site conditions, the following parameters are being monitored: instrument temperature and battery voltage; barometric pressure and temperature; meteorological parameters; water level, wellhead pressure, water temperature; radon in free gas phase; CO2 concentration and CO2 flux in soil gas. Data are transmitted hourly via FTP to GFZ. While we generally observe small seasonal variations, short-term transients related to heavy rain or local and distant earthquakes are indicated. Over longer periods, we observe trend changes in helium isotope ratios, radon concentration, and water temperature. For example, two sites exhibited significant helium isotope changes from 2021 to 2025, which appear to correlate with earthquake swarms at depth. These examples demonstrate the necessity of jointly interpreting meteorological, hydrogeological, geophysical, and geodetic data.