Tracing subducted crust in the oceanic mantle with siderophile elements and transition metal stable isotopes and implications for the sources of basaltic volcanism

• Applicant: Professorin Dr. Ambre Luguet, since 11/2016
• Subject Area: Mineralogy, Petrology and Geochemistry
• Term: from 2015 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 277251666

In order to understand global material fluxes between crust and mantle, the fate of subducted oceanic crust and its contribution to mantle-derived volcanism needs to be constrained. Pyroxenites have been suggested to be products of interaction of melts derived from subducted crust and to be an important component in the source region of oceanic basalts in the lithosphere. To develop a more complete understanding of the processes controlling the distribution of tracers during melt-rock interaction, a combined study of highly siderophile elements (HSE, including Os isotopes) and stable isotopes of transition metals (Fe, Cu, Ni) on both the whole rock and individual grain scale in pyroxenite layers and their immediate surroundings is proposed. Pyroxenites from the External Ligurides, Italy, which have been demonstrated to contain crust-derived material, are ideally suited for this type of study. Highly siderophile elements and stable isotopes of Fe have been developed as useful tools to study interaction of melts with surrounding wall rock in the mantle, and coupled with development of Ni and Cu isotopes as mantle tracers will provide new insights about the distribution of sulfide-hosted elements during melt-rock interaction.

• DFG Programme: Research Grants
• International Connection: Belgium, Italy, United Kingdom
• Cooperation Partners: Professorin Dr. Vinciane Debaille; Professor Dr. Raúl Fonseca; Professorin Dr. Alessandra Montanini; Dr. Geoff Nowell
• Ehemaliger Antragsteller: Dr. David van Acken, until 10/2016