POSTER PRESENTATION
The oxidation state of the subcontinental lithospheric mantle (SCLM) is often estimated by measurements of oxygen fugacity (ƒO2) using methods such as Mössbauer Spectroscopy or XANES to measure Fe3+/Fe2+ in mantle xenoliths. While precise and accurate, these approaches can be limited by the availability of equipment or samples (e.g., weathered environments); thus, the development of alternative redox proxies is desirable. As peridotitic garnets can carry elements such as V and Cr with differences in valence states and partition coefficients, easily determined by EMP or LA-ICP-MS, Cr-pyrope xenocrysts often recovered in heavy mineral concentrates become a suitable monomineralic ƒO2 proxy.
In this contribution, we evaluate V/Sc in garnet (V/Scgnt) as a new oxybarometer for SCLM domains. We investigate how oxygen fugacity and other factors such as element partitioning, temperature, pressure and metasomatism might affect the V/Sc trend in garnets from lithospheric domains representing various tectonothermal age ranges (i.e., Archon (A), Proton (P), Tecton (T) and their combinations; see Begg et al., 2009).
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