Isotope and and trace element studies of the Xingdi II mafic-ultramafic   complex in the northern rim of the Tarim Craton: Evidence for   emplacement in a Neoproterozoic subduction zone

doi:10.1016/j.lithos.2017.01.014

CORC > 北京大学 > 地球与空间科学学院

	Isotope and and trace element studies of the Xingdi II mafic-ultramafic complex in the northern rim of the Tarim Craton: Evidence for emplacement in a Neoproterozoic subduction zone
	Chen, Hongjin ; Chen, Yanjing ; Ripley, Edward M. ; Li, Chusi ; Deng, Xiaohua ; Yue, Suwei ; Zheng, Zhen ; Fu, Bin
刊名	LITHOS
	2017
关键词	Mafic-ultramafic rocks Mantle plume Subduction Tarim Craton Rodinia PB ZIRCON GEOCHRONOLOGY SOUTH CHINA NW CHINA YANGTZE BLOCK MANTLE PLUME CARBONATITE COMPLEX MASS-SPECTROMETRY KULUKETAGE BLOCK IGNEOUS ACTIVITY NORTHWEST CHINA
DOI	10.1016/j.lithos.2017.01.014
英文摘要	The Xingdi II mafic-ultramafic complex is located in the northern rim of the Tarim Craton, Northern Xinjiang, NW China.This complex is mainly composed of gabbro, gabbronorite, websterite and lherzolite, plus minor granodiorites and granites. The geodynamic setting of this complex and other Neoproterozoic mafic-ultramafic complexes in the region is debated, with opinions varying from mantle plume to a continental arc A new zircon U-Pb age from this study reveals >7-myr difference for two gabbroic intrusive phases in the Xingdi II mafic-ultramafic complex and up to a 21-myr difference between this complex and the nearby mafic-ultramafic complexes that occur <12 km from this complex. The age changes for the Neoproterozoic (730-820 Ma) mafic-ultramafic complexes in the area occur in different directions and hence a mantle plume origin for the complexes is unlikely. The Xingdi II mafic-ultramafic intrusive rocks are characterized by moderate light-REE enrichments and pronounced negative Nb anomaly, which are common for mafic-ultramafic rocks in convergent tectonic settings, and negative epsilon Nd(t) values ( -9.2 to -5.1) and elevated initial Sr-87/Sr-86 ratios (0.7061 to 0.7086), which indicate enriched source mantle plus crustal contamination. The epsilon Hf(t) values of zircon crystals from the Xingdi II mafic-ultramafic complex are between -2.8 and -7.0. The trace element and isotope data together indicate that this complex formed from multiple pulses of contaminated subduction-related basaltic magma that were emplaced separately with a time gap of at least 7 myr. The results from this study support the viewpoint that in the Neoproterozoic the northern rim of the Tarim Craton was an active continental margin that belongs to the Circum-Rodinia Subduction System. (C) 2017 Elsevier B.V. All rights reserved.; China Geological Survey Bureau [1212011140056]; China Scholarship Council [201506010049]; SCI(E); ARTICLE; 274-284; 278
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/473778]
专题	地球与空间科学学院
推荐引用方式 GB/T 7714	Chen, Hongjin,Chen, Yanjing,Ripley, Edward M.,et al. Isotope and and trace element studies of the Xingdi II mafic-ultramafic complex in the northern rim of the Tarim Craton: Evidence for emplacement in a Neoproterozoic subduction zone[J]. LITHOS,2017.
APA	Chen, Hongjin.,Chen, Yanjing.,Ripley, Edward M..,Li, Chusi.,Deng, Xiaohua.,...&Fu, Bin.(2017).Isotope and and trace element studies of the Xingdi II mafic-ultramafic complex in the northern rim of the Tarim Craton: Evidence for emplacement in a Neoproterozoic subduction zone.LITHOS.
MLA	Chen, Hongjin,et al."Isotope and and trace element studies of the Xingdi II mafic-ultramafic complex in the northern rim of the Tarim Craton: Evidence for emplacement in a Neoproterozoic subduction zone".LITHOS (2017).