Tectonic evolution and continental crust growth of Northern Xinjiang in   northwestern China: Remnant ocean model

doi:10.1016/j.earscirev.2013.08.005

CORC > 北京大学 > 地球与空间科学学院

	Tectonic evolution and continental crust growth of Northern Xinjiang in northwestern China: Remnant ocean model
	Xu, Qin-Qin ; Ji, Jian-Qing ; Zhao, Lei ; Gong, Jun-Feng ; Zhou, Jing ; He, Guo-Qi ; Zhong, Da-Lai ; Wang, Jin-Duo ; Griffiths, Lee
刊名	earth science reviews
	2013
关键词	Ophiolite Geochemistry Remnant ocean Continental crust growth Northern Xinjiang ASIAN OROGENIC BELT APATITE FISSION-TRACK ND ISOTOPIC EVIDENCE CARBONIFEROUS VOLCANIC-ROCKS WEST JUNGGAR REGION A-TYPE GRANITES NW CHINA TIEN-SHAN TIANSHAN MOUNTAINS SR-ND
DOI	10.1016/j.earscirev.2013.08.005
英文摘要	The Northern Xinjiang region is located in the southwestern part of the Central Asian Orogenic Belt (CAOB, also known as the Altaid Tectonic Collage). Despite extensive research aimed at understanding the crustal growth of the CAOB and the evolution of the Paleo-Asian Ocean, the tectonic evolution mechanism of continental crust growth in Northern Xinjiang remains controversial. The geology of Northern Xinjiang is characterized by widespread ophiolites, granitoids, intermediate-basic dikes. Most of the ophiolites were generated in the early Paleozoic. The ophiolites are widely spread around the Junggar Basin, but their distribution does not indicate a well-defined band. Their outcrops are generally related to various faults. The basic rocks widespread in Northern Xinjiang are grouped into two categories: (i) gabbros, diabases basalts of the ophiolites and (ii) basic dikes that intrude into the Paleozoic strata granite plutons. The basic rocks associated with the early Paleozoic ophiolites were reworked by later geothermal events with a peak Ar-40/Ar-39 age of 310-290 Ma. The basic dikes intruded into Paleozoic strata and granite plutons during the Carboniferous-Jurassic, displaying three peaks of emplacement at 260-250 Ma, 220 Ma, and 200-190 Ma. These two types of basic rocks and the documented Variscan magmatic rocks were derived from the same source. Their isotope geochemical characteristics and widespread distribution suggest that since the Paleozoic, a large geochemical province has existed in Northern Xinjiang with an affinity to mid-ocean ridge basalts (MORB) and ocean island basalts (OIB), which is related to a long-lived remnant ocean and the underlying early Paleozoic oceanic crust. The existence of remnant oceanic crust in Northern Xinjiang was confirmed by seismic, gravity and aeromagnetic data. Therefore, we propose the following remnant ocean model for the Paleozoic tectonic evolution of Northern Xinjiang. It consists of three stages: 1) oceanic crust formation and deposition of the overlying volcanic-sedimentary rocks during the early Paleozoic; 2) retaining of the remnant ocean with marine sediments deposited during the early stage of the late Paleozoic; and 3) widespread and pervasive emplacement of Variscan granites, intermediate-basic dikes, and their volcanic equivalents during the Late Carboniferous and Early Permian, and termination of marine sedimentation at the end of the Early Permian. The tectonic evolution of Northern Xinjiang has been in a state of intracontinental deformation since the Mesozoic The Variscan granitoids and basic dikes of Northern Xinjiang originated from the partial melting of the remnant oceanic crust formed in the early Paleozoic. These Variscan intrusive rocks represent the production of continental crust transferred from the basic crust The Phanerozoic continental growth of Northern Xinjiang was completed by mass transfer from the early Paleozoic remnant oceanic crust; this approach may considerably change our views of continental growth. (C) 2013 Elsevier B.V. All rights reserved.; Geosciences, Multidisciplinary; SCI(E); 0; ARTICLE; 178-205; 126
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/155628]
专题	地球与空间科学学院
推荐引用方式 GB/T 7714	Xu, Qin-Qin,Ji, Jian-Qing,Zhao, Lei,et al. Tectonic evolution and continental crust growth of Northern Xinjiang in northwestern China: Remnant ocean model[J]. earth science reviews,2013.
APA	Xu, Qin-Qin.,Ji, Jian-Qing.,Zhao, Lei.,Gong, Jun-Feng.,Zhou, Jing.,...&Griffiths, Lee.(2013).Tectonic evolution and continental crust growth of Northern Xinjiang in northwestern China: Remnant ocean model.earth science reviews.
MLA	Xu, Qin-Qin,et al."Tectonic evolution and continental crust growth of Northern Xinjiang in northwestern China: Remnant ocean model".earth science reviews (2013).