Fe3+ content of experimental pyroxenes and melt analyzed with in-situ synchrotron Mössbauer spectroscopy v.2
Abstract:
An accurate understanding of the partition coefficients of Fe3+ and Fe2+ between silicate minerals and melts (DFe3+, DFe2+, and DFe3+/DFe2+) is required to quantify redox variations during magmatic processes. However, the mineral/melt DFe3+ and DFe2+ are sparsely reported due to the difficulties in determining Fe3+ content of the minerals in quenched experimental run products. Recent progress in the use of synchrotron radiation sources has developed new frontiers in the study of Fe3+ partitioning between minerals and melts. In this study, we analyzed Fe3+ content of experimentally synthesized pyroxenes and melt with the in-situ synchrotron Mössbauer spectroscopy using a beam size < 10 μm and determined accurate DFe3+ and DFe2+ for orthopyroxene (opx), clinopyroxene (cpx), and spinel (spl) crystallized at the equilibrium pressure and temperature of 1.3 GPa and 1200 °C. The obtained DFe3+ values are 0.62 (±0.02) for opx, 0.96 (±0.03) for cpx, and 6.79 (±0.28) for spl. The corresponding DFe2+ are 1.05 (±0.03) for opx, 0.53 (±0.01) for cpx, and 2.96 (±0.08) for spl. The DFe3+/DFe2+ ratios, calculated from paired DFe3+ and DFe2+ values, are 0.59 (±0.02) for opx, 1.85 (±0.07) for cpx, and 2.29 (±0.04) for spl. It is, therefore, expected that during partial melting of spinel lherzolite in a closed system, the consumption of opx will decrease Fe3+/FeT and fO2 of the magma. In contrast, the consumption of cpx and spl has the opposite effect. A preliminary modeling, based on these partition coefficients, shows that partial melting of an ordinary sub-arc mantle with Fe3+/FeT of 3.7% cannot account for the elevated Fe3+/FeT of primitive arc basalts, suggesting that arc basalts inherited the oxidizing signature from intrinsically oxidized mantle sources.
How to cite this dataset:
Wang, J., Marras, G., Stagno, V., 2025. Fe3+ content of experimental pyroxenes and melt analyzed with in-situ synchrotron Mössbauer spectroscopy v.2, Version 1.0. Interdisciplinary Earth Data Alliance (IEDA).
https://doi.org/10.60520/IEDA/113848. Accessed 2025-06-16.
DOI Creation Date:
2025-06-11
Related
Publication(s):
Wang et al., Determination of Fe3+ and Fe2+ partition coefficients between pyroxenes and basaltic melt with in-situ synchrotron Mössbauer spectroscopy. J Pet (In revision)
License:
Creative Commons Attribution 4.0 International [CC-BY-4.0]
Funding source(s):
HERMES project, 2022R35X8Z
National Natural Science Foundation of China, 42003047 and 42273037
Keyword(s):
Coverage Scope: Other
Geographic Location: High pressure experiments, magma generation and differentiation
User Contributed Keyword(s):
Synchrotron Mössbauer spectroscopy, Partitioning of Fe3+ and Fe2+, Pyroxenes/basaltic melt, Redox variations, sub-arc mantle melting
Data Available On:
2025-06-13