Rhenium elemental and isotopic variations at magmatic temperatures
Abstract
Recent analytical advances in the measurement of rhenium (Re) isotope ratios allow its potential as a palaeoredox and chemical weathering proxy to be explored. However, a successful isotopic proxy must be grounded by an understanding of its composition and behaviour in the solid Earth. Here, we present Re concentrations and Re isotopic (δ187Re) compositions for a well-characterised sequence of lavas from Hekla volcano, Iceland. The concentration of Re varies from 0.02 to 1.4 ng/g, decreasing from basalt to more evolved lavas. We show that the crystallisation and removal of magnetite is responsible for the Re decrease in this system. By contrast, δ187Re values for the same suite of samples show a relatively narrow range (−0.45 to −0.22 0/1000), suggesting minimal resolvable Re isotope fractionation between magnetite and the silicate melt. Together with other samples, including mid-ocean ridge basalts, these first igneous data can be used to estimate a baseline for terrestrial materials (δ187Re = −0.33 ± 0.15 0/1000, 2 s.d., n = 14), from which low-temperature Re isotope variations in Earth’s surficial environments can be assessed, alongside the global isotope mass balance of Re.
Citation
Wang , W , Dickson , A J , Stow , M A , Dellinger , M , Burton , K W , Savage , P S , Hilton , R G & Prytulak , J 2024 , ' Rhenium elemental and isotopic variations at magmatic temperatures ' , Geochemical Perspectives Letters , vol. 28 , pp. 48-53 . https://doi.org/10.7185/geochemlet.2402
Publication
Geochemical Perspectives Letters
Status
Peer reviewed
ISSN
2410-339XType
Journal article
Description
This work was funded by Natural Environment Research Council UK Standard Grant to RGH, AJD, and JP (NE/T001119).Collections
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