The Archean Park team (from left: Ivan Berg, Jens Kallmeyer, Kai-Uwe Hinrichs, Alexander Probst).

In the ERC project Archean Park, organic geochemist Kai-Uwe Hinrichs (FB5/MARUM), together with his colleagues Ivan Berg (University of Münster), Jens Kallmeyer (GFZ Potsdam) and Alexander Probst (University of Duisburg-Essen), will investigate how the extremely high atmospheric CO2 concentrations in the Archean eon - the period thought to have witnessed the origin of microbial life on Earth - affected microbial metabolic processes. The central hypothesis is that microbial relicts of ancient carbon fixation pathways still exist at modern CO2-rich sites, where they can be discovered and studied. To this end, the team is planning extensive fieldwork in areas in the Eifel, the Czech Republic and Italy, all of which host environments with subsurface volcanic CO2 degassing. In his now third ERC project, Hinrichs and his Bremen team are planning extensive geochemical analyses of microbial metabolites in environmental samples and microbial cultures. These data will provide crucial information about the metabolic carbon cycling under extremely high CO2 concentrations. In addition to basic research on microbial carbon fixation, the Archean Park project will provide baseline information on the influence of future CO2 injections on microbial ecosystems in the subsurface.