气候变化领域集成服务门户(CCPortal): Petrogenesis of the early Paleozoic strongly peraluminous granites in the Western South China Block and its tectonic implications

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DOI	10.1016/j.jseaes.2014.11.022
	Petrogenesis of the early Paleozoic strongly peraluminous granites in the Western South China Block and its tectonic implications
	Peng, Touping; Fan, Weiming; Zhao, Guochun; Peng, Bingxia; Xia, Xiaoping; Mao, Yongsheng
通讯作者	Peng, TP (通讯作者)
发表日期	2015
ISSN	1367-9120
EISSN	1878-5786
起始页码	399
结束页码	420
卷号	98
英文摘要	( Strongly peraluminous (SP) granites have A/CNK (molecular Al2O3/(CaO+Na2O+K2O)) ratios >1.1, indicating a predominant origin from the partial melting of metasedimentary rocks. However, an increasing number of studies have documented that mantle-derived magmas can also be involved in the petrogenesis of some SP granites. This is the case in the Dulong batholith in the southeastern Yunnan province, southwestern South China Block, which is typically composed of SP granitic rocks with high A/CNK values (>1.1). Zircon U-Pb dating of four samples from this batholith yielded consistent crystallization ages of ca. 430 Ma, synchronous with the widespread late-orogenic magmatism (including S- and I-type granites and mafic igneous rocks) in the Wuyi-Yunkai orogen, South China Block (SCB). All the granites have fractionated REE patterns ((LalYb)(N) = 1.28-12.3) and conspicuous negative Eu anomalies (Eu*/Eu = 00.07-0.43) with a similar depletion in HFSE (Nb, Zr, Hf), P, Ba and Sr, suggesting that these granitic magmas had a dominantly crustal source, likely the Neoproterozoic metasedimentary rocks (i.e., the Danzhou or Banxi groups) that are dominated by pelitic rocks with minor interlayered siltstones in the western Yangtze Block. However, their zircon Hf isotopic results also reveal an important input of the mantlederived melts into their parental magma. Taken together, their geochemical and isotopic compositions reflect a derivation by magma mixing between the crust- and mantle-derived (similar to 10% in volume) magmas. Their chemical variations resulted from the fractionation process during the emplacement from the magma chamber after magmatic mixing. In conjunction with regional data within the SCB, it is most likely that the magmatism younger than 435 Ma was generated in a post-collisional extensional regime related to the partial delamination of an overthickened lithospheric mantle root without lower crust. (C) 2014 Elsevier Ltd. All rights reserved.
关键词	U-PB GEOCHRONOLOGY LACHLAN FOLD BELT S-TYPE GRANITES MAFIC MICROGRANULAR ENCLAVES PLASMA-MASS SPECTROMETRY HF ISOTOPE GEOCHEMISTRY WUYI-YUNKAI OROGEN I-TYPE GRANITES TRACE-ELEMENT SOUTHEASTERN CHINA
英文关键词	Dulong batholith; Strongly peraluminous granite; Early Paleozoic; Magma mixing; South China Block
语种	英语
WOS研究方向	Geology
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:000348955800030
来源期刊	JOURNAL OF ASIAN EARTH SCIENCES
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/258533
推荐引用方式 GB/T 7714	Peng, Touping,Fan, Weiming,Zhao, Guochun,et al. Petrogenesis of the early Paleozoic strongly peraluminous granites in the Western South China Block and its tectonic implications[J]. 中国科学院青藏高原研究所,2015,98.
APA	Peng, Touping,Fan, Weiming,Zhao, Guochun,Peng, Bingxia,Xia, Xiaoping,&Mao, Yongsheng.(2015).Petrogenesis of the early Paleozoic strongly peraluminous granites in the Western South China Block and its tectonic implications.JOURNAL OF ASIAN EARTH SCIENCES,98.
MLA	Peng, Touping,et al."Petrogenesis of the early Paleozoic strongly peraluminous granites in the Western South China Block and its tectonic implications".JOURNAL OF ASIAN EARTH SCIENCES 98(2015).