Geothermal fluids and their interactions with rocks and materials are in the research focus of this working group. Geothermal fluids are gas-water mixtures from deep geological formations that typically contain a large amount of salts. Research on those fluids is challenging due to their complex composition and the rough conditions of their occurrence (high temperatures, pressures, and salinities).
In the working team, we are interested on the origin and migration pathways of the fluids and examine geochemical processes under those extreme conditions (e.g. within the EU project REFLECT). Furthermore, methods for risk minimization during geothermal plant operation are developed (e.g. in the EU project PERFORM). Besides deep geothermal energy systems, we also look at geochemical processes in the underground occurring during aquifer thermal energy storage (e.g. in the BMWi projects ATES-GeoFern, ATES-IQ).
While the focus so far was more on the risks of fluid components for geothermal plant operation, we investigate now also the benefits that are provided by the fluids, especially in terms of the extraction of economically valuable components from the brine.
Our labs are equipped with high pressure and temperature resistant equipment (autoclaves, flow-through devices and sensors). We also developed special mobile fluid monitoring devices and maintain a mobile XRF to perform in-situ field experiments directly at geothermal sites.
As the carrier of heat, geothermal fluids play a fundamental role in all deep underground processes. As such the themes examined by the working group are cross cutting topics and we collaborate closely with other teams of the Geoenergy Section (e.g. fluidphysics, reservoir engineering, monitoring) as well as with other sections at GFZ that deal with geomicrobiology, organic and inorganic chemistry, and geochemical modeling.