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The key role of mica during igneous concentration of tantalum
journal contribution
posted on 2023-05-18, 03:20 authored by Stepanov, A, Mavrogenes, JA, Sebastien MeffreSebastien Meffre, Paul DavidsonPaul DavidsonIgneous rocks with high Ta concentrations share a number of similarities such as high Ta/Nb, low Ti, LREE and Zr concentrations and granitic compositions. These features can be traced through fractionated granitic series. Formation of Ta-rich melts begins with anatexis in the presence of residual biotite, followed by magmatic crystallization of biotite and muscovite. Crystallization of biotite and muscovite increases Ta/Nb and reduces the Ti content of the melt. Titanium-bearing oxides such as rutile and titanite are enriched in Ta and have the potential to deplete Ta at early stages of fractionation. However, mica crystallization suppresses their saturation and allows Ta to increase in the melt. Saturation with respect to Ta and Nb minerals occurs at the latest stages of magmatic crystallization, and columbite can originate from recrystallization of mica. We propose a model for prediction of intrusion fertility for Ta.
History
Publication title
Contributions to Mineralogy and PetrologyVolume
167Issue
6Article number
1009Number
1009Pagination
1-8ISSN
0010-7999Department/School
School of Natural SciencesPublisher
Springer-VerlagPlace of publication
175 Fifth Ave, New York, USA, Ny, 10010Rights statement
Copyright 2014 Springer-Verlag Berlin HeidelbergRepository Status
- Restricted