Geochemistry and geochronology of high-grade rocks from the Grove Mountains, East Antarctica Evidence for an Early Neoproterozoic basement metamorphosed during a single Late Neoproterozoic/Cambrian tectonic cycle

CORC > 中国地质调查局 > 中国地质调查局

	Geochemistry and geochronology of high-grade rocks from the Grove Mountains, East Antarctica Evidence for an Early Neoproterozoic basement metamorphosed during a single Late Neoproterozoic/Cambrian tectonic cycle
	Liu, XC (Liu, Xiaochun); Jahn, BM (Jahn, Bor-Ming); Zhao, Y (Zhao, Yue); Zhao, GC (Zhao, Guochun); Liu, XH (Liu, Xiaohan)
刊名	PRECAMBRIAN RESEARCH
	2007
卷号	158 期号:1-2 页码:93-118
关键词	early neoproterozoic matic-felsic intrusion late Neoproterozoic/Cambrian single metamorphic cycle grove mountains prydz belt East Antarctica
ISSN号	0301-9268
英文摘要	The Grove Mountains of East Antarctica are an inland continuation of the Prydz Belt. The high-grade metarnorphic complex in this area is composed of felsic orthogneisses and mafic granulites, with minor paragneisses and calc-silicate rocks. U-Pb zircon analyses using SHRIMP and LA-ICP-MS techniques reveal that the protoliths of mafic granulites and felsic orthogneisses were emplaced during a short time interval of ca. 920-910 Ma. Mafic granulites can be divided into low- and high-Ti groups. They have initial epsilon(Nd) values [epsilon(Nd)(T)] ranging from +0.8 to -1.9. TiO2 is positively correlated with FeOt/MgO and La/Nb ratios, whereas it shows a negative correlation with epsilon(Nd)(T) values, indicating that the petrogenesis of their protoliths involved partial melting of a weakly enriched subcontinental lithospheric mantle and fractional crystallization of the magma accompanied by minor crustal contamination. Felsic orthogneisses have an affinity of A(2)-type granites, characterized by enrichment in REE, Y, Zr, Th and Ga and high Ga/Al and Y/Nb ratios. Most of them have epsilon(Nd)(T) values of -0.7 to -3.5 and Nd depleted mantle model ages (Tom) of 1.76-1.65 Ga, and a few have low epsilon(Nd)(T) values of -10.4to -10.6 and old T-DM of 2.46-2.27Ga, reflecting a heterogeneity in their source region. Their protoliths were probably produced by high-temperature partial melting of tonalitic-granodioritic rocks triggered by the underplating of mantle-derived matic magma during post-orogenic extension. U-Pb analyses also reveal a metamorphic age of ca. 2050 Ma from detrital zircons in a paragneiss, suggesting that the sedimentary materials of the paragneiss may have come from an as yet undiscovered Early Paleoproterozoic orogen of unknown provenance. Voluminous mafic-felsic intrusives and a small amount of sedimentary rocks constitute an Early Neoproterozoic basement of the Grove Mountains. Subsequently, this basement experienced only a single Late Neoproterozoic/Cambrian metamorphic cycle at ca. 550-535 Ma. The available data indicate that the Prydz Belt is a collage of multiple basement terranes and each of them has a distinct tectonic evolution. This supports the suggestion that the Prydz Belt may represent a Late Neoproterozoic/Cambrian collisional orogen that resulted in the final phase of the Gondwana assembly. (c) 2007 Elsevier B.V. All rights reserved.
学科主题	变质岩岩石学
WOS关键词	PRINCE-CHARLES MOUNTAINS ; CAMBRIAN OROGENIC BELT ; ZONE SOUTHERN ALPS ; U-PB GEOCHRONOLOGY ; LARSEMANN-HILLS ; TRACE-ELEMENT ; PRYDZ-BAY ; SRI-LANKA ; BRATTSTRAND BLUFFS ; CRUSTAL EVOLUTION
WOS研究方向	Geology
语种	英语
出版者	ELSEVIER SCIENCE BV
WOS记录号	WOS:000249482900005
内容类型	期刊论文
源URL	[http://119.78.100.197/handle/2HKVOGP0/38547]
专题	中国地质调查局
作者单位	Chinese Acad Geol Sci, Inst Geomech, Beijing 100081, Peoples R China Acad Sinica, Inst Earth Sci, Taipei 11529, Taiwan Natl Taiwan Univ, Dept Geol Sci, Taipei 106, Taiwan Univ Hong Kong, Dept Earth Sci, Hong Kong, Hong Kong, Peoples R China Chinese Acad Sci, Inst Geol & Geophys, Beijing 100029, Peoples R China
推荐引用方式 GB/T 7714	Liu, XC ,Jahn, BM ,Zhao, Y ,et al. Geochemistry and geochronology of high-grade rocks from the Grove Mountains, East Antarctica Evidence for an Early Neoproterozoic basement metamorphosed during a single Late Neoproterozoic/Cambrian tectonic cycle[J]. PRECAMBRIAN RESEARCH,2007,158(1-2):93-118.
APA	Liu, XC ,Jahn, BM ,Zhao, Y ,Zhao, GC ,&Liu, XH .(2007).Geochemistry and geochronology of high-grade rocks from the Grove Mountains, East Antarctica Evidence for an Early Neoproterozoic basement metamorphosed during a single Late Neoproterozoic/Cambrian tectonic cycle.PRECAMBRIAN RESEARCH,158(1-2),93-118.
MLA	Liu, XC ,et al."Geochemistry and geochronology of high-grade rocks from the Grove Mountains, East Antarctica Evidence for an Early Neoproterozoic basement metamorphosed during a single Late Neoproterozoic/Cambrian tectonic cycle".PRECAMBRIAN RESEARCH 158.1-2(2007):93-118.