气候变化领域集成服务门户(CCPortal): High magnesian schist, granitic gneiss, amphibolite and monzogneiss in the eastern Ama Drime Massif in South Tibet (China): A rifted Paleoproterozoic arc fringed the western Columbia supercontinent?

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DOI	10.1016/j.precamres.2023.106972
	High magnesian schist, granitic gneiss, amphibolite and monzogneiss in the eastern Ama Drime Massif in South Tibet (China): A rifted Paleoproterozoic arc fringed the western Columbia supercontinent?
	Li, Rui; Xiao, Wenjiao; Mao, Qigui; Zhang, Ji'en; Ao, Songjian; Song, Dongfang; Tan, Zhou; Wang, Hao; Bhandari, Saunak
发表日期	2023
ISSN	0301-9268
EISSN	1872-7433
卷号	388
英文摘要	Understanding the Paleoproterozoic tectonic setting of the north Indian Craton-as either continental rifting or continent arc-is vital for locating the Indian Craton in the Columbia supercontinent. Herein, we present new petrological, geochemical, Nd-Hf isotopic, and geochronological data of high magnesian schist, granitic gneiss, amphibolite and biotite monzogneiss in the south-eastern margin of the Ama Drime Massif of South Tibet (China). The high magnesian schist contains 20.4 %-31.3 % phlogopite, 12.2 %-17.8 % clinochlorite, 10.5 %- 13.4 % cordierite and 5.5 %-5.6 % loss on ignition, implying its protolith of Mg-rich clays and later alteration in the fault zone. Its medium-silicic composition and concentrative magmatic zircon age of ca. 1859 Ma indicates the origin of the clays from locally deposited mafic rocks. Moreover, its negative values of ENd(t) (-3.0 to-2.6) and zircon EHf(t) (-8.6 to +2.4) correspond to the metavolcanic rock in the same outcrop as well. Granitic gneiss, amphibolite and biotite monzogneiss exhibit their protolith of crystal ages between 1870 and 1849 Ma with characteristics of negative anomalies of Nb, Ta, and Ti in subduction zone setting. They have similar negative values of ENd(t) (-3.0 to-1.3) and zircon EHf(t) (-8.6 to +4.0), indicating various degrees of contamination in the continental crust. The geochemical characteristics of the granitic gneiss and amphibolite signify the generation of their protolith via various degrees (1.5-2.5 %) of partial melting of spinel lherzolite inside the shallow mantle. As the high alkalinity of biotite monzogneiss implies a greater contribution of water from the subduction plate, and the trace elements of zircons manifest their affinity of continent arc toward island arc, we interpret the origin of the protolith of these rocks in a setting of continental arc-related rifting at the north of the Indian Craton. The finding of this arc reinforces that the reconstruction of the western Columbia super-continent was fringed with an active margin.
关键词	Paleoproterozoic arc Ama Drime Magnesian schist Zircon U-Pb age Geochemistry Columbia supercontinent
英文关键词	TRACE-ELEMENT COMPOSITION; IN-SITU ANALYSIS; U-PB; LU-HF; ZIRCON MEGACRYSTS; MANTLE; EVOLUTION; HIMALAYA; ND; DISCRIMINATION
WOS研究方向	Geosciences, Multidisciplinary
WOS记录号	WOS:000952477200001
来源期刊	PRECAMBRIAN RESEARCH
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/283384
作者单位	Chinese Academy of Sciences; Xinjiang Institute of Ecology & Geography, CAS; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS; Chinese Academy of Sciences; Institute of Geology & Geophysics, CAS; Chinese Academy of Sciences
推荐引用方式 GB/T 7714	Li, Rui,Xiao, Wenjiao,Mao, Qigui,et al. High magnesian schist, granitic gneiss, amphibolite and monzogneiss in the eastern Ama Drime Massif in South Tibet (China): A rifted Paleoproterozoic arc fringed the western Columbia supercontinent?[J],2023,388.
APA	Li, Rui.,Xiao, Wenjiao.,Mao, Qigui.,Zhang, Ji'en.,Ao, Songjian.,...&Bhandari, Saunak.(2023).High magnesian schist, granitic gneiss, amphibolite and monzogneiss in the eastern Ama Drime Massif in South Tibet (China): A rifted Paleoproterozoic arc fringed the western Columbia supercontinent?.PRECAMBRIAN RESEARCH,388.
MLA	Li, Rui,et al."High magnesian schist, granitic gneiss, amphibolite and monzogneiss in the eastern Ama Drime Massif in South Tibet (China): A rifted Paleoproterozoic arc fringed the western Columbia supercontinent?".PRECAMBRIAN RESEARCH 388(2023).