气候变化领域集成服务门户(CCPortal): Late Neoproterozoic/Cambrian high-pressure mafic granulites from the Grove Mountains, East Antarctica: P-T-t path, collisional orogeny and implications for assembly of East Gondwana

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DOI	10.1016/j.precamres.2009.07.001
	Late Neoproterozoic/Cambrian high-pressure mafic granulites from the Grove Mountains, East Antarctica: P-T-t path, collisional orogeny and implications for assembly of East Gondwana
	Liu, Xiaochun; Hu, Jianmin; Zhao, Yue; Lou, Yuxing; Wei, Chunjing; Liu, Xiaohan
通讯作者	Liu, XC (通讯作者)
发表日期	2009
ISSN	0301-9268
EISSN	1872-7433
起始页码	181
结束页码	199
卷号	174 期号:1-2
英文摘要	The Grove Mountains are an inland continuation of the Late Neoproterozoic/Cambrian Prydz Belt of East Antarctica. In this paper we report high-pressure (HP) mafic granulites that occur in glacial moraines from this area. Petrographical textures, mineral compositions and P-T pseudosection calculations in the system NCFMASHTO (Na2O-CaO-FeO-MgO-Al2O3-SiO2-H2O-TiO2-Fe2O3) suggest that the HP mafic granulites record peak P-T conditions of 11.8-14.0 kbar and 770-840 degrees C. The post-peak evolution of these rocks involved near-isothermal decompression of ca. 6 kbar followed by a greenschist facies overprint. SHRIMP U-Pb zircon dating, coupled with the identification of mineral inclusion assemblage in zircons, reveals HP metamorphism occurred at ca. 545 Ma and subsequent retrograde reactions involving near-isothermal decompression at ca. 530 Ma. Garnet-clinopyroxene-whole-rock Sm-Nd isotopic analyses also yield Cambrian 'isochron' ages. This reflects collision at a convergent plate margin followed by extensional exhumation as the orogen collapsed during Late Neoproterozoic/Cambrian orogeny. Therefore, the occurrence of HP mafic granulites from the Grove Mountains provides evidence for a collisional tectonic setting for the Prydz Belt, which supports the notion that East Gondwana was not finally assembled until the Cambrian. (C) 2009 Elsevier B.V. All rights reserved.
关键词	PRINCE-CHARLES MOUNTAINS MINERAL EQUILIBRIA CALCULATIONS PRYDZ-BAY RAUER-GROUP U-PB LARSEMANN HILLS POLYMETAMORPHIC TERRANE METAPELITIC GRANULITES METASEDIMENTARY ROCKS CONTINENTAL COLLISION
英文关键词	East Antarctica; Prydz Belt; Late Neoproterozoic/Cambrian; HP mafic granulite; Collisional orogeny
语种	英语
WOS研究方向	Geology
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:000271362800012
来源期刊	PRECAMBRIAN RESEARCH
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/257682
推荐引用方式 GB/T 7714	Liu, Xiaochun,Hu, Jianmin,Zhao, Yue,et al. Late Neoproterozoic/Cambrian high-pressure mafic granulites from the Grove Mountains, East Antarctica: P-T-t path, collisional orogeny and implications for assembly of East Gondwana[J]. 中国科学院青藏高原研究所,2009,174(1-2).
APA	Liu, Xiaochun,Hu, Jianmin,Zhao, Yue,Lou, Yuxing,Wei, Chunjing,&Liu, Xiaohan.(2009).Late Neoproterozoic/Cambrian high-pressure mafic granulites from the Grove Mountains, East Antarctica: P-T-t path, collisional orogeny and implications for assembly of East Gondwana.PRECAMBRIAN RESEARCH,174(1-2).
MLA	Liu, Xiaochun,et al."Late Neoproterozoic/Cambrian high-pressure mafic granulites from the Grove Mountains, East Antarctica: P-T-t path, collisional orogeny and implications for assembly of East Gondwana".PRECAMBRIAN RESEARCH 174.1-2(2009).