Late Carboniferous adakitic granodiorites in the Qiongkusitai area, western Tianshan, NW China: Implications for partial melting of lower crust in the southern Central Asian Orogenic Belt

	Late Carboniferous adakitic granodiorites in the Qiongkusitai area, western Tianshan, NW China: Implications for partial melting of lower crust in the southern Central Asian Orogenic Belt
	Jiyuan Yin; Wen Chen; Wenjiao Xiao; Chao Yuan; Xiaoping Long; Keda Cai; Bin Zhang
	2016
Source Publication	Journal of Asian Earth Sciences
Volume	124 Issue:1 Pages:42-54
Abstract	Carboniferous granitic rocks are wide spread in the western Tianshan, but their tectonic contexts remain controversial. We present zircon U-Pb age, major element, trace element, and in situ zircon Hf isotopic data for the Qiongkusitai granodiorites from the southern part of the Yili block in the western Tianshan. The granodiorites were emplaced in the Late Carboniferous (ca. 314 Ma) and are characterized by high SiO2 (62.1-65.7 wt.%), high Sr (376-485 ppm), low Y (13.7-17.7 ppm) and low Yb (1.34-1.81 ppm) with Sr/Y ratios of 23-34. Such characteristics imply adakitic affinities. Their low concentrations of Cr (3.85-6.75 ppm), Co (7.63-10.7 ppm) and Ni (2.94-6.80 ppm) suggest little, if any, interaction with a mantle source. Compared to the thickened lower crustal-derived adakitic rocks, the relatively low Nb/Ta ratios of the Qiongkusitai adakitic granodiorites indicate that they were probably generated by partial melting of amphibolite fades rocks, but not eclogite fades rocks. The Qiongkusitai adakitic granodiorites have positive zircon epsilon(Hf(t)) values of +0.7 to +5.1 and T-DM2 of 1.28-1.68 Ga, and they are interpreted as being derived from remelting of amphibolite facies Mesoproterozoic basement with an input of juvenile material. Late Carboniferous magmatism in the western Tianshan was possibly triggered by asthenospheric upwelling as a result of the roll-back of the subducted southern Tianshan oceanic lithosphere.
Keyword	Adakitic Granodiorite Slab Roll-back Partial Melting Of Lower Crust West Tianshan Carboniferous
Subject Area	矿床地球化学
Indexed By	SCI
Language	英语
Document Type	期刊论文
Identifier	http://ir.gyig.ac.cn/handle/352002/6219
Collection	矿床地球化学国家重点实验室_矿床地球化学国家重点实验室_期刊论文
Recommended Citation GB/T 7714	Jiyuan Yin,Wen Chen,Wenjiao Xiao,et al. Late Carboniferous adakitic granodiorites in the Qiongkusitai area, western Tianshan, NW China: Implications for partial melting of lower crust in the southern Central Asian Orogenic Belt[J]. Journal of Asian Earth Sciences,2016,124(1):42-54.
APA	Jiyuan Yin.,Wen Chen.,Wenjiao Xiao.,Chao Yuan.,Xiaoping Long.,...&Bin Zhang.(2016).Late Carboniferous adakitic granodiorites in the Qiongkusitai area, western Tianshan, NW China: Implications for partial melting of lower crust in the southern Central Asian Orogenic Belt.Journal of Asian Earth Sciences,124(1),42-54.
MLA	Jiyuan Yin,et al."Late Carboniferous adakitic granodiorites in the Qiongkusitai area, western Tianshan, NW China: Implications for partial melting of lower crust in the southern Central Asian Orogenic Belt".Journal of Asian Earth Sciences 124.1(2016):42-54.

Files in This Item:
There are no files associated with this item.

If you have any objections to this item, please fill out the form below and the administrator will contact you as soon as possible.
Content:
Email：	*
Institution:
Verification Code:	Refresh

Any comments and suggestions are welcomed.
Title:	*
Content:
Email：	*
Verification Code:	Refresh

矿床地球化学国家重点实验室知识库