Implications for Rodinia reconstructions for the initiation of Neoproterozoic subduction at similar to 860 Ma on the western margin of the Yangtze Block: Evidence from the Guandaoshan Pluton

doi:10.1016/j.lithos.2014.03.002

	Implications for Rodinia reconstructions for the initiation of Neoproterozoic subduction at similar to 860 Ma on the western margin of the Yangtze Block: Evidence from the Guandaoshan Pluton
	Du, Lilin 1; Guo, Jinghui 1; Nutman, Allen P.; Wyman, Derek 3; Geng, Yuansheng ; Yang, Chonghui ; Liu, Fulai ; Ren, Liudong ; Zhou, Xiwen
刊名	LITHOS
	2014
卷号	196 页码:67-82
关键词	Yangtze Block Neoproterozoic Guandaoshan pluton SHRIMP zircon U-Pb dating Island arc
ISSN号	0024-4937
DOI	10.1016/j.lithos.2014.03.002
英文摘要	Neoproterozoic igneous rocks are widespread along the western margin of the Yangtze Block, but their petrogenesis and tectonic setting is debated. The Guandaoshan pluton is located at the southwestern margin of the Yangtze Block and is mainly composed of diorite and subordinate gabbro, with quartz diorite in its margin. Hornblende is an ubiquitous mineral in different phases of the pluton. SHRIMP zircon U-Pb dating of quartz diorite, gabbroic diorite, and gabbro from the pluton yielded Pb-206/U-238 ages of 857 +/- 7 Ma, 856 +/- 6 Ma, and 856 +/- 8 Ma, respectively. Guandaoshan pluton samples show a large range of SiO2 (47.02-67.66%), MgO (1.12-7.5%), Fe2O3T (2.8-12.22%) and CaO (2.95-11.88%), low rare earth element (REE) contents from 22 to 49 ppm, and enrichment of Sr, Ba and Rb and depletion of Nb, Zr and Ti with characteristics of island arc magma. They also exhibit low initial Sr-87/Sr-86 ratios from 0.7030-0.7033, and positive epsilon(Nd)(t) values from +4.8 to +52. These features suggest that the parental magma of the Guandaoshan pluton originated at a convergent plate boundary from a depleted mantle source modified by slab fluids, and underwent the fractional crystallization of amphibole and magnetite, without significant crustal assimilation, during the formation from gabbro-diorite to quartz diorite. Neoproterozoic magmas with age of 860-740 Ma are abundant on the western Yangtze Block, and there is a gap of magmatism in early Neoproterozoic (from about 1000 Ma to 870 Ma). Therefore, it can be deduced that the similar to 860 Ma Guandaoshan pluton and the contemporary magmatism represent initial subduction at the western margin of the Yangtze Block. Based on the Neoproterozoic paleomagnetic data, detrital zircon ages, magmas with low delta O-18 values in South China and our new data, we prefer that the South China Block was located at the margin of Rodinia in the Neoproterozoic, and not at the center of the supercontinent. (C) 2014 Elsevier B.V. All rights reserved.
学科主题	构造地质学
WOS关键词	U-PB GEOCHRONOLOGY ; NORTH CHINA CRATON ; SOUTHERN SICHUAN PROVINCE ; SUB-ARC MANTLE ; CONTINENTAL-CRUST ; JIANGNAN OROGEN ; SW CHINA ; TRACE-ELEMENT ; TECTONIC SIGNIFICANCE ; ZIRCON GEOCHRONOLOGY
WOS研究方向	Geochemistry & Geophysics ; Mineralogy
语种	英语
出版者	ELSEVIER SCIENCE BV
WOS记录号	WOS:000336347800006
内容类型	期刊论文
源URL	[http://119.78.100.197/handle/2HKVOGP0/40531]
专题	中国地质科学院地质研究所
作者单位	1.Chinese Acad Geol Sci, Inst Geol, Beijing 100037, Peoples R China 2.Chinese Acad Sci, Inst Geol & Geophys, Beijing 100029, Peoples R China 3.Nutman, Allen P.] Univ Wollongong, GeoQuEST Res Ctr, Sch Earth & Environm Sci, Wollongong, NSW 2522, Australia 4.Univ Sydney, Sch Geosci, Sydney, NSW 2006, Australia
推荐引用方式 GB/T 7714	Du, Lilin,Guo, Jinghui,Nutman, Allen P.,et al. Implications for Rodinia reconstructions for the initiation of Neoproterozoic subduction at similar to 860 Ma on the western margin of the Yangtze Block: Evidence from the Guandaoshan Pluton[J]. LITHOS,2014,196:67-82.
APA	Du, Lilin.,Guo, Jinghui.,Nutman, Allen P..,Wyman, Derek.,Geng, Yuansheng.,...&Zhou, Xiwen.(2014).Implications for Rodinia reconstructions for the initiation of Neoproterozoic subduction at similar to 860 Ma on the western margin of the Yangtze Block: Evidence from the Guandaoshan Pluton.LITHOS,196,67-82.
MLA	Du, Lilin,et al."Implications for Rodinia reconstructions for the initiation of Neoproterozoic subduction at similar to 860 Ma on the western margin of the Yangtze Block: Evidence from the Guandaoshan Pluton".LITHOS 196(2014):67-82.