Die Eisen- und Sulfid-reiche Arvadi-Mineralwasser-Quelle (Schweiz) als Modell für biogeochemische Prozesse im paläoproterozoischen Ozean

• Antragsteller: Professor Dr. Andreas Kappler; Professor Ronny Schönberg, Ph.D.; Professor Dr. Harald Strauß
• Fachliche Zuordnung: Mineralogie, Petrologie und Geochemie
• Förderung: Förderung von 2014 bis 2019
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 234745564

The evolution of redox conditions in the Paleoproterozoic atmosphere and hydrosphere, in particular the first appearance of O2, is controversially debated. Sulfur and iron are redox sensitive and isotope analyses of Fe and S compounds in ancient sediments are therefore used to constrain redox conditions and biogeochemical processes present at the time of rock formation. This research project aims at unraveling the Paleoproterozoic oceanic biogeochemistry by studying the inorganic and microbial cycling of Fe and S and their geochemical and isotopic consequences in the Arvadi spring (Engadin/Switzerland). This spring, with its unique co-existence of dissolved Fe(II) and H2S, but the absence of FeS precipitation, provides an opportunity to assess the relative contribution of abiotic compared to microbial sulfur and iron redox transformations and mineral precipitation. The results obtained from the 'Arvadi natural laboratory' will be used to evaluate and refine existing models of Paleoproterozoic ocean biogeochemistry.

• DFG-Verfahren: Sachbeihilfen