MSc Luise Wagner, Dr. Ilka Kleinhanns & Prof. Dr. Ronny Schoenberg

Non-traditional stable isotopes can be useful tracers to investigate the physical and chemical evolution of the Earth’s mantle. During high temperature processes chromium mainly exists in two oxidation states, Cr²⁺ and Cr³⁺, and isotopic fractionation may therefore be controlled by both, igneous processes such as partial melting and fractional crystallization, as well as intensive parameters such as the prevailing oxygen fugacity.

This project aims at investigating the behavior of stable Cr isotopic fractionation during these processes by studying different basaltic reservoirs (modern MORB and OIB, and Archean komatiite-tholeiite suites). Analyses of stable Cr isotopes are complemented by stable Fe isotopes , radiogenic Sr-Nd-Pb isotope signatures as well as major and trace elements of the sample suites involved in this project.

Ultimately, a better understanding of stable Cr isotope systematics in high temperature systems will improve our understanding of changing oxygen fugacities in magmatic systems.

Funding: German Research Foundation (DFG)

Collaborators:

• Dr. Mike G. Babechuk (Canada, Memorial University of Newfoundland)
• Prof. Dr. Axel Hofmann (South Africa, University of Johannesburg)
• Prof. Dr. Olivier Rouxel (France, IFREMER)
• Prof. Dr. Gerhard Woerner (Germany, University of Goettingen)
• Prof. Dr. Wolfgang Bach (Germany, University of Bremen)

Student Projects:

• Nadja Weber (BSc 2019, University of Tuebingen)
• Isabel Anthony (BSc 2019, University of Tuebingen)
• Clara Zelinsky (BSc ongoing, University of Tuebingen)