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DOI	10.1016/j.jseaes.2017.06.012
	Ultramafic to mafic granulites from the Larsemann Hills, East Antarctica: Geochemistry and tectonic implications
	Tong, Laixi; Jahn, Bor-ming; Liu, Xiaohan; Liang, Xirong; Xu, Yi-gang; Ionov, Dmitri
通讯作者	Tong, LX (通讯作者)
发表日期	2017
ISSN	1367-9120
EISSN	1878-5786
起始页码	679
结束页码	690
卷号	145
英文摘要	The Larsemann Hills area is part of a reworked early Neoproterozoic metamorphic terrain in southwestern Prydz Bay, East Antarctica. Ultramafic and mafic granulites, whose origins remain controversial, occur as lenses, boudins or layered bodies within the para- and ortho-gneiss in the region. The ultramafic and mafic granulites show spinel-olivine-bearing and two-pyroxene-bearing mineral assemblages recrystallized at 860-900 degrees C. Their bulk rock analyses indicate an origin as igneous cumulates, with high Mg-# (molar MgO/(MgO + FeO)) from 0.73 to 0.84 for ultramafic granulite and from 0.46 to 0.78 for mostly mafic granulite as well as high Cr and Ni contents ([Cr] and [Ni] up to 1826 ppm and 1400 ppm respectively for ultramafic granulite and [Cr] of 1460 ppm for mafic granulite). Trace element patterns show pronounced negative Nb anomalies, suggesting a subduction-related tectonic setting for their precursors, consistent with derivation from arc basalts, also suggested by low TiO2 and K-enrichment in mafic granulites. The ultramafic to mafic granulites may have been formed in a subduction-related continental back-arc basin environment simultaneously with peak metamorphism associated with arc-continent collision during the early Neoproterozoic (990-900 Ma) Rayner orogeny.
关键词	PRINCE-CHARLES MOUNTAINS AMERY ICE SHELF PRYDZ-BAY RAUER GROUP FACIES METAMORPHISM BRATTSTRAND BLUFFS CONTINENTAL-CRUST VESTFOLD BLOCK U-PB EVOLUTION
英文关键词	Ultramafic to mafic granulites; Geochemistry; Rayner orogeny (990-900 Ma); Larsemann Hills; East Antarctica
语种	英语
WOS研究方向	Geology
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:000411533600026
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/259002
推荐引用方式 GB/T 7714	Tong, Laixi,Jahn, Bor-ming,Liu, Xiaohan,et al. Ultramafic to mafic granulites from the Larsemann Hills, East Antarctica: Geochemistry and tectonic implications[J]. 中国科学院青藏高原研究所,2017,145.
APA	Tong, Laixi,Jahn, Bor-ming,Liu, Xiaohan,Liang, Xirong,Xu, Yi-gang,&Ionov, Dmitri.(2017).Ultramafic to mafic granulites from the Larsemann Hills, East Antarctica: Geochemistry and tectonic implications.JOURNAL OF ASIAN EARTH SCIENCES,145.
MLA	Tong, Laixi,et al."Ultramafic to mafic granulites from the Larsemann Hills, East Antarctica: Geochemistry and tectonic implications".JOURNAL OF ASIAN EARTH SCIENCES 145(2017).