دورية أكاديمية
Thermodynamic controls on element partitioning between titanomagnetite and andesitic–dacitic silicate melts
| العنوان: | Thermodynamic controls on element partitioning between titanomagnetite and andesitic–dacitic silicate melts |
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| المؤلفون: | Sievwright, RH, Wilkinson, JJ, O'Neill, HSC, Berry, AJ |
| بيانات النشر: | SpringerLink |
| سنة النشر: | 2020 |
| المجموعة: | Natural History Museum Repository |
| مصطلحات موضوعية: | Magnetite, Trace-element partitioning, Andesite, Dacite, Oxygen fugacity, Petrogenetic indicator |
| الوصف: | Titanomagnetite–melt partitioning of Mg, Mn, Al, Ti, Sc, V, Co, Ni, Cu, Zn, Ga, Zr, Nb, Mo, Hf and Ta was investigated experimentally as a function of oxygen fugacity (fO2) and temperature (T) in an andesitic–dacitic bulk-chemical compositional range. In these bulk systems, at constant T, there are strong increases in the titanomagnetite–melt partitioning of the divalent cations (Mg2+, Mn2+, Co2+, Ni2+, Zn2+) and Cu2+/Cu+ with increasing fO2 between 0.2 and 3.7 log units above the fayalite–magnetite–quartz buffer. This is attributed to a coupling between magnetite crystallisation and melt composition. Although melt structure has been invoked to explain the patterns of mineral–melt partitioning of divalent cations, a more rigorous justification of magnetite–melt partitioning can be derived from thermodynamic principles, which accounts for much of the supposed influence ascribed to melt structure. The presence of magnetite-rich spinel in equilibrium with melt over a range of fO2 implies a reciprocal relationship between a(Fe2+O) and a(Fe3+O1.5) in the melt. We show that this relationship accounts for the observed dependence of titanomagnetite–melt partitioning of divalent cations with fO2 in magnetite-rich spinel. As a result of this, titanomagnetite–melt partitioning of divalent cations is indirectly sensitive to changes in fO2 in silicic, but less so in mafic bulk systems. ; Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0Test/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The attached file is the published pdf. ; NHM Repository |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| تدمد: | 0010-7999 1432-0967 |
| العلاقة: | http://rdcu.be/t09ATest; Sievwright, R.H., Wilkinson, J.J., O’Neill, H.S.C. et al. Thermodynamic controls on element partitioning between titanomagnetite and andesitic–dacitic silicate melts. Contrib Mineral Petrol 172, 62 (2017). https://doi.org/10.1007/s00410-017-1385-6Test; http://hdl.handle.net/10141/622768Test; Contributions to Mineralogy and Petrology; 172; 62 |
| DOI: | 10.1007/s00410-017-1385-6 |
| الإتاحة: | https://doi.org/10.1007/s00410-017-1385-6Test http://hdl.handle.net/10141/622768Test |
| حقوق: | openAccess ; http://creativecommons.org/licenses/by/4.0Test/ |
| رقم الانضمام: | edsbas.5148840F |
| قاعدة البيانات: | BASE |
| تدمد: | 00107999 14320967 |
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| DOI: | 10.1007/s00410-017-1385-6 |