Geochronology, geochemistry and petrogenesis of the Kongwusayi A-type granites in the eastern Alataw Mountain, West Tianshan, Xinjiang

被引：0

作者：

Lin T. ^{[1
,2
]}

Deng Y. ^{[1
,3
]}

Chen B. ^{[1
,4
]}

Wang Z. ^{[1
,3
]}

Sun K. ^{[5
]}

Zhao B. ^{[1
]}

机构：

[1] School of Resources and Environmental Engineering, Hefei University of Technology, Hefei

[2] The Second Institute of Hydrology and Engineering Geological Prospecting of Anhui Geological Prospecting Bureau, Wuhu, 241000, Anhui

[3] Anhui Province Engineering Research Center for Mineral Resources and Mine Environments, Hefei

[4] Department of Earth and Space Sciences, Southern University of Science and Technology, Shenzhen, 518055, Guangdong

[5] School of Earth Scienes and Resources, China University of Geosciences, Beijing

来源：

Dizhi Xuebao/Acta Geologica Sinica | 2019年 / 93卷 / 05期

关键词：

A-type granite; Alataw Mountain; Oxygenfugacity; Petrogenesis; U-Pb chronology of zircon;

D O I：

10.19762/j.cnki.dizhixuebao.2019051

中图分类号：

学科分类号：

摘要：

The Kongwusayi granitic pluton is located in the south slope and east side of the Alataw Mountain, West Tianshan of Xinjiang. The pluton is composed mainly of alkali-feldspar granite, coarse grained K-feldspar granite and fine grained K-feldspar granite. The weighted average U-Pb age of zircons in the alkali-feldspar granite and the fine grained K-feldspar granite are 293.1±3.6 Ma and 293±3.7 Ma, respectively. The three types of granites belong to aluminum-weakly peraluminous and high potassium calcium alkaline series. Eu negative anomalies increase quickly from the alkali feldspar granite to the coarse grained K-feldspar granite and the fine grained K-feldspar granite, and depletion degree of Ba, Sr, P, Ti and the enrichment degree of Rb, Th, U are gradually increasing, indicating a tendency of crystallization differentiation between the three magma types. These granites are enriched in Ga with high 104Ga/Al (2.6~3.5), Fe* (0.88~0.97) and TiO2/MgO (0.51~1.25), suggesting that they are characteristic of A-type granites. A-type granites in the study area are characterzied by the high saturation temperature of zircons (853. 86~931. 56℃) and low Ce(Ⅳ)/Ce(Ⅲ) (1.9~77), implying that the A-type granites were formed in higher temperature and lower oxygen fugacity conditions. The Kongwusayi granites have higher Y content (43.3×10-6~106×10-6), higher εNd(t) (+3.0~+5.2) and lower (87Sr/86Sr)i (0.7027~0.7069), suggesting that the Kongwusayi A-type granites may formed by the partial melting of the basaltic crust. By comparing with the carboniferous basalt in West Tianshan, the Kongwusayi A-type granites display lower εNd(t) and higher (87Sr/86Sr)i, indicating the magma source of the kongwusayi A-type granites may include the ancient crustal materials. © 2019, Science Press. All right reserved.

引用

页码：1020 / 1036

页数：16

共 60 条

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