Geochronology, petrology and Sr-Nd-Hf-S isotope geochemistry of the newly-discovered Qixin magmatic Ni-Cu sulfide prospect, southern Central Asian Orogenic Belt, NW China

doi:10.1016/j.oregeorev.2019.103002

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

	Geochronology, petrology and Sr-Nd-Hf-S isotope geochemistry of the newly-discovered Qixin magmatic Ni-Cu sulfide prospect, southern Central Asian Orogenic Belt, NW China
	Xue, Shengchao 1; Li, Chusi 2; Wang, Qingfei 1; Ripley, Edward M.2; Yao, Zhuosen 3
刊名	ORE GEOLOGY REVIEWS
	2019-08-01
卷号	111 页码:18
关键词	Qixin mafic-ultramafic complex Ni-Cu sulfide mineralization Zircon U-Pb age Sr-Nd-Hf-S isotopes Central Asian Orogenic Belt
ISSN号	0169-1368
DOI	10.1016/j.oregeorev.2019.103002
英文摘要	The Qixin mafic-ultramafic complex is present in the southern margin of the Central Asian Orogenic Belt in northern Xinjiang where many magmatic Ni-Cu sulfide deposits occur. To determine the temporal association of the newly-discovered Ni-Cu prospect associated with the Qixin complex with the known major magmatic Ni-Cu sulfide deposits in the region, as well as the origin of sulfide mineralization in the Qixin complex, we have carried out geochronological, petrological and geochemical studies of this complex. Gabbro, olivine gabbro, norite, olivine gabbronorite, troctolite, websterite and lherzolite are the major rock types of this complex. Two drill cores completed to date show two types of sulfide mineralization associated with the complex: (1) disseminated sulfides that occur near the base of bodies of lherzolite and troctolite; (2) blotchy-massive sulfides in the homfels country rocks. The disseminated sulfides are composed of pyrrhotite, pentlandite and chalcopyrite, whereas the blotchy-massive sulfides in the country rocks are composed of pentlandite, violarite, pyrrhotite and chalcopyrite. Zircon crystals from the Qixin olivine gabbronorite yield a U-Pb age of 286.5 +/- 2.5 Ma, which is among the oldest post-subduction magmatic Ni-Cu sulfide deposits in the region. The TiO2/Al2O3 ratios of Crspinel and clinopyroxene from the Qixin complex are similar to those from the older, subduction-related mafic-ultra-mafic intrusions in the region. This and other arc-like geochemical characteristics such as whole-rock negative Nb-Ta anomalies coupled with low initial Sr-87/Sr-86 (0.7036-0.7057), positive epsilon(Nd)(t) ( + 2.3 to + 6.0) and high epsilon(Hf)(t) of zircon ( + 8.3 to + 15), indicate that the parental magma of the Qixin complex was derived from a mantle source modified by pre-Permian metasomatic processes, similar to other contemporaneous mafic-ultramafic intrusions in the region. Mixing calculations using Sr-Nd-Hf isotopes indicate that the parental magma for the Qixin mafic-ultramafic rocks experienced no more than 15 wt% contamination with siliceous country rocks. The delta S-34 values of different sulfide assemblages of the Qixin Ni-Cu prospect are similar and vary from 1.1 to 1.7%o, which are within the range of typical mantle values as well as that of the country rocks, providing no direct evidence for addition of external sulfur. However, the role of external sulfur in sulfide mineralization at Qixin still cannot be ruled out, as forward modelling indicates that fractional crystallization plus crustal contamination involving siliceous country rocks free of S could not have induced sulfide saturation in the Qixin magma. This may also be true for the contemporaneous magmatic Ni-Cu sulfide deposits in the region. Based on the results from this study, we suggest that fractures in the solid country rocks nearby the Qixin complex and the ultramafic bodies of the complex are preferred targets if exploration continues.
资助项目	National Basic Research Program of China[2015CB452602] ; National Basic Research Program of China[2009CB421008] ; Natural Science Foundation of China[41802076] ; China Postdoctoral Science Foundation[2016M600109]
WOS关键词	MAFIC-ULTRAMAFIC INTRUSION ; LARGE IGNEOUS PROVINCE ; PALEOZOIC CRUSTAL GROWTH ; PLATINUM-GROUP ELEMENT ; ZIRCON U-PB ; EASTERN TIANSHAN ; BEISHAN AREA ; HUANGSHANDONG INTRUSION ; CONTINENTAL GROWTH ; TECTONIC EVOLUTION
WOS研究方向	Geology ; Mineralogy ; Mining & Mineral Processing
语种	英语
出版者	ELSEVIER
WOS记录号	WOS:000484869200029
资助机构	National Basic Research Program of China ; National Basic Research Program of China ; Natural Science Foundation of China ; Natural Science Foundation of China ; China Postdoctoral Science Foundation ; China Postdoctoral Science Foundation ; National Basic Research Program of China ; National Basic Research Program of China ; Natural Science Foundation of China ; Natural Science Foundation of China ; China Postdoctoral Science Foundation ; China Postdoctoral Science Foundation ; National Basic Research Program of China ; National Basic Research Program of China ; Natural Science Foundation of China ; Natural Science Foundation of China ; China Postdoctoral Science Foundation ; China Postdoctoral Science Foundation ; National Basic Research Program of China ; National Basic Research Program of China ; Natural Science Foundation of China ; Natural Science Foundation of China ; China Postdoctoral Science Foundation ; China Postdoctoral Science Foundation
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/93559]
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	Xue, Shengchao
作者单位	1.China Univ Geosci, State Key Lab Geol Proc & Mineral Resources, Beijing 100083, Peoples R China 2.Indiana Univ, Dept Earth & Atmospher Sci, Bloomington, IN 47405 USA 3.Chinese Acad Sci, Inst Geol & Geophys, Key Lab Mineral Resources, Beijing 100029, Peoples R China
推荐引用方式 GB/T 7714	Xue, Shengchao,Li, Chusi,Wang, Qingfei,et al. Geochronology, petrology and Sr-Nd-Hf-S isotope geochemistry of the newly-discovered Qixin magmatic Ni-Cu sulfide prospect, southern Central Asian Orogenic Belt, NW China[J]. ORE GEOLOGY REVIEWS,2019,111:18.
APA	Xue, Shengchao,Li, Chusi,Wang, Qingfei,Ripley, Edward M.,&Yao, Zhuosen.(2019).Geochronology, petrology and Sr-Nd-Hf-S isotope geochemistry of the newly-discovered Qixin magmatic Ni-Cu sulfide prospect, southern Central Asian Orogenic Belt, NW China.ORE GEOLOGY REVIEWS,111,18.
MLA	Xue, Shengchao,et al."Geochronology, petrology and Sr-Nd-Hf-S isotope geochemistry of the newly-discovered Qixin magmatic Ni-Cu sulfide prospect, southern Central Asian Orogenic Belt, NW China".ORE GEOLOGY REVIEWS 111(2019):18.