Granulite-grade garnet pyroxenite from the Kolli-massif, southern India: Implications for Archean crustal evolution

doi:10.1016/j.lithos.2019.05.040

CORC > 地质与地球物理研究所 > 中国科学院地质与地球物理研究所 > 中国科学院矿产资源研究重点实验室

	Granulite-grade garnet pyroxenite from the Kolli-massif, southern India: Implications for Archean crustal evolution
	George, P. M.1,2; Sajeev, K.2; Santosh, M.3,4; Zhai, M.1,5
刊名	LITHOS
	2019-10-01
卷号	342 页码:499-512
关键词	Garnet pyroxenite Granulite Kolli-massif Southern India Crustal evolution Archean
ISSN号	0024-4937
DOI	10.1016/j.lithos.2019.05.040
英文摘要	Pyroxenite is a relatively rare but important rock type of mafic-ultramafic series, and provides a useful tool to understand deep crustal and crust mantle processes. Here we present petrology, phase equilibrium modelling and P-T estimates, zircon U-Pb geochronology and Hf isotopes on a recent find of garnet websterite from the Jambumalai hillock, Kolli-massif, southern India. The rock types in this location include metamorphosed orthopyroxenite, clinopyroxenite, garnet websterite and garnetite among which, garnet websterite is the most abundant variety. Petrological studies show that the peak metamorphic mineral assemblage of the garnet websterite is Grt + Cpx + Opx +/- Ilm. The garnet is Fe rich (X-Mg = 039-0.41) whereas the clinopyroxene composition varies from augite to sub-augite (X-Mg = 0.72-0.79). The orthopyroxene shows a compositional range between ferrosilite and hypersthene (X-Mg = 0.61-64). Clinopyroxene in some of the garnet websterite samples exhibits exsolution microstructure with blebs of orthopyroxene. The orthopyroxene is Ca poor and Fe rich and displays the features of 'inverted pigeonite'. Phase-equilibria modelling in the NCFMASH system yielded a P-T estimate of c.22 Kbar and c.980 degrees C. Zircon U-Pb analysis using SIMS yielded a weighted mean age of 2526 +/- 38 Ma, which is regarded as the age of metamorphism. Zircon Lu-Hf isotope data shows initial epsilon Hf values between +2 and -7.7, indicating a dominantly reworked crustal source for the protolith. Our results suggest high pressure and high temperature metamorphism at the base of a thickened Archean continental crust. (C) 2019 Elsevier B.V. All rights reserved.
资助项目	Govt. of India: Department of Science and Technology[SR/S4/ES-594/2011] ; Govt. of India: Department of Science and Technology[NT/SLP/P-004] ; Govt. of India: Department of Science and Technology[DST/INT/JSPS/P-167/13] ; Ministry of Earth Sciences[MoES/P.O. (Geosci)/26/2014] ; State Key Laboratory for Continental Dynamics, Department of Geology, Northwest University
WOS关键词	ZIRCON U-PB ; WESTERN DHARWAR CRATON ; CAUVERY SHEAR ZONE ; ULTRAHIGH-TEMPERATURE METAMORPHISM ; HIGH-PRESSURE GRANULITES ; LU-HF ; CONTINENTAL-CRUST ; NILGIRI BLOCK ; LITHOSPHERIC MANTLE ; TRACE-ELEMENT
WOS研究方向	Geochemistry & Geophysics ; Mineralogy
语种	英语
出版者	ELSEVIER
WOS记录号	WOS:000477091500032
资助机构	Govt. of India: Department of Science and Technology ; Ministry of Earth Sciences ; State Key Laboratory for Continental Dynamics, Department of Geology, Northwest University ; Govt. of India: Department of Science and Technology ; Ministry of Earth Sciences ; State Key Laboratory for Continental Dynamics, Department of Geology, Northwest University ; Govt. of India: Department of Science and Technology ; Ministry of Earth Sciences ; State Key Laboratory for Continental Dynamics, Department of Geology, Northwest University ; Govt. of India: Department of Science and Technology ; Ministry of Earth Sciences ; State Key Laboratory for Continental Dynamics, Department of Geology, Northwest University
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/92966]
专题	地质与地球物理研究所_中国科学院矿产资源研究重点实验室
通讯作者	George, P. M.
作者单位	1.Northwest Univ, Dept Geol, State Key Lab Continental Dynam, Xian 710069, Shaanxi, Peoples R China 2.Indian Inst Sci, Ctr Earth Sci, Bengaluru 560012, India 3.China Univ Geosci, Sch Earth Sci & Resources, Xueyuan Rd 29, Beijing 100083, Peoples R China 4.Univ Adelaide, Dept Earth Sci, Adelaide, SA 5005, Australia 5.Chinese Acad Sci, Inst Geol & Geophys, Key Lab Mineral Resources, Beijing 100029, Peoples R China
推荐引用方式 GB/T 7714	George, P. M.,Sajeev, K.,Santosh, M.,et al. Granulite-grade garnet pyroxenite from the Kolli-massif, southern India: Implications for Archean crustal evolution[J]. LITHOS,2019,342:499-512.
APA	George, P. M.,Sajeev, K.,Santosh, M.,&Zhai, M..(2019).Granulite-grade garnet pyroxenite from the Kolli-massif, southern India: Implications for Archean crustal evolution.LITHOS,342,499-512.
MLA	George, P. M.,et al."Granulite-grade garnet pyroxenite from the Kolli-massif, southern India: Implications for Archean crustal evolution".LITHOS 342(2019):499-512.