An experimental study of the partitioning of trace elements between rutile and silicate melt as a function of oxygen fugacity

Date

2014

Authors

Mallmann, Guilherme
Fonseca, R
Silva, Adolfo Barbosa

Journal Title

Journal ISSN

Volume Title

Publisher

Academia Brasileira de Ciencias

Abstract

Subduction zone or arc magmas are known to display a characteristic depletion of High Field Strength Elements (HFSE) relative to other similarly incompatible elements, which can be attributed to the presence of the accessory mineral rutile (TiO2) in the residual slab. Here we show that the partitioning behavior of vanadium between rutile and silicate melt varies from incompatible (~0.1) to compatible (~18) as a function of oxygen fugacity. We also confirm that the HFSE are compatible in rutile, with D(Ta) > D(Nb) >> (D(Hf) >/~ D(Zr), but that the level of compatibility is strongly dependent on melt composition, with partition coefficients increasing about one order of magnitude with increasing melt polymerization (or decreasing basicity). Our partitioning results also indicate that residual rutile may fractionate U from Th due to the contrasting (over 2 orders of magnitude) partitioning between these two elements. We confirm that, in addition to the HFSE, Cr, Cu, Zn and W are compatible in rutile at all oxygen fugacity conditions.

Description

Keywords

Keywords: Arc magma; HFSE; Partition coeffcient; Redox; Rutile

Citation

Source

Anais da Academia Brasileira de Ciencias

Type

Journal article

Book Title

Entity type

Access Statement

Open Access

License Rights

DOI

10.1590/0001-3765201420140014

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