The interplay between magma redox and magma differentiation in arc settings: phase equilibrium constraints and the development of new oxybarometers

My Ph.D. project aims at developing new methods to trace the evolution of the redox state of magmas during magma differentiation. The goal is to use the exchange coefficients of heterovalent and similar monovalent elements (e.g. V and Sc) between silicate melt and typical igneous phenocrysts (e.g. olivine, pyroxenes, and amphibole) as an indicator of magmatic oxygen fugacity. With appropriate experimental calibration obtained through this project, measured compositions of silicate melt inclusion – host mineral pairs in natural samples could yield fO2 estimates, and therefore it would become possible to reconstruct the temporal evolution of the redox state of magmas. This is very important not only for igneous petrology in general but also for the understanding the ore fertility of magmatic systems.