US EPA

4837096 

Journal Article 

Geochronology and magma oxygen fugacity of Ehu S-type granitic pluton in Zhe-Gan-Wan region, SE China 

Qiu, JunT; Qiu, L 

2016 

Yes 

Chemie der Erde: Geochemistry
ISSN: 0009-2819
EISSN: 1611-5864 

76 

3 

441-448 

10.1016/j.chemer.2016.06.004 

WOS:000385320400009 

In this paper, we determined the U-Pb isotopic and trace element compositions of zircons from the Ehu S-type granite in the Zhe-Gan-Wan region, SE China, using in-situ laser ablation (LA) ICP-MS. The weighted mean (206)pb/U-238 age of 132.0 +/- 0.6 Ma for the Ehu granite indicates that the pluton was formed in the Early Cretaceous and during the Late Mesozoic Cu-Mo mineralization quiescence in Zhe-Gan-Wan region. The calculated logarithmic magma oxygen fugacities for Ehu granite range from -19.19 to -11.43 with an average magma oxidation state of FMQ-0.29, which is much lower than those of Cu-Mo bearing granites in the Zhe-Gan-Wan region. Since Ehu granite was derived from partial melting of metasedimentary basement without fractional crystallization and mantle-derived magma contamination, the low oxidation state of this granite suggests that the assimilation of metasedimentary basement component may not significantly increase the oxidation state of reduced melts from asthenospheric mantle and could not generate oxidized magmas that are favorable for Cu-Mo mineralization. (C) 2016 Elsevier GmbH. All rights reserved. 

Magma oxygen fugacity; Zircon; Ehu pluton; Cu-Mo mineralization; Zhe-Gan-Wan region