Iron Isotope Fractionation during Skarn Cu-Fe Mineralization

doi:10.3390/min11050444

CORC > 海洋研究所 > 中国科学院海洋研究所

	Iron Isotope Fractionation during Skarn Cu-Fe Mineralization
	Xue, Song 2; Niu, Yaoling 2,4,5; Chen, Yanhong 2; Shi, Yining 2; Xia, Boyang 2; Wang, Peiyao 1,3,4; Gong, Hongmei 1,3,4; Wang, Xiaohong 1,3,4; Duan, Meng 1,3,4
刊名	MINERALS
	2021-05-01
卷号	11 期号:5 页码:18
关键词	porphyry-skarn deposits Fe isotopes isotopic fractionation pathway effects light-Fe fluid redox state
DOI	10.3390/min11050444
通讯作者	Xue, Song(song.x@cugb.edu.cn) ; Niu, Yaoling(yaoling.niu@durham.ac.uk)
英文摘要	Fe isotopes have been applied to the petrogenesis of ore deposits. However, the behavior of iron isotopes in the mineralization of porphyry-skarn deposits is still poorly understood. In this study, we report the Fe isotopes of ore mineral separations (magnetite, pyrite, chalcopyrite and pyrrhotite) from two different skarn deposits, i.e., the Tonglvshan Cu-Fe skarn deposit developed in an oxidized hydrothermal system and the Anqing Cu skarn deposit developed in a reduced hydrothermal system. In both deposits, the Fe isotopes of calculated equilibrium fluids are lighter than those of the intrusions responsible for the skarn and porphyry mineralization, corroborating the "light-Fe fluid" hypothesis. Interestingly, chalcopyrite in the oxidized-Tonglvshan skarn deposit has lighter Fe than chalcopyrite in the reduced-Anqing skarn deposit, which is best understood as the result of the prior precipitation of magnetite (heavy Fe) from the ore fluid in the oxidized-Tonglvshan systems and the prior precipitation of pyrrhotite (light Fe) from the ore fluid in the reduced-Anqing system. The delta Fe-56 for pyrite shows an inverse correlation with delta Fe-56 of magnetite in the Tonglvshan. In both deposits, the Fe isotope fractionation between chalcopyrite and pyrite is offset from the equilibrium line at 350 degrees C and lies between the FeS-chalcopyrite equilibrium line and pyrite-chalcopyrite equilibrium line at 350 degrees C. These observations are consistent with the FeS pathway towards pyrite formation. That is, Fe isotopes fractionation during pyrite formation depends on a path from the initial FeS-fluid equilibrium towards the pyrite-fluid equilibrium due to the increasing extent of Fe isotopic exchange with fluids. This finding, together with the data from other deposits, allows us to propose that the pathway effect of pyrite formation in the Porphyry-skarn deposit mineralization is the dominant mechanism that controls Fe isotope characteristics.
资助项目	National Natural Science Foundation (NSFC)[41630968] ; National Natural Science Foundation (NSFC)[91958215] ; NSFC-Shandong Joint Fund for Marine Science Research Centers[U1606401] ; 111 project[B18048]
WOS研究方向	Geochemistry & Geophysics ; Mineralogy ; Mining & Mineral Processing
语种	英语
出版者	MDPI
WOS记录号	WOS:000662438300001
内容类型	期刊论文
源URL	[http://ir.qdio.ac.cn/handle/337002/176921]
专题	中国科学院海洋研究所
通讯作者	Xue, Song; Niu, Yaoling
作者单位	1.Chinese Acad Sci, Ctr Ocean Megasci, 7 Nanhai Rd, Qingdao 266071, Peoples R China 2.China Univ Geosci, Sch Earth Sci & Resources, Beijing 100083, Peoples R China 3.Chinese Acad Sci, Inst Oceanol, Qingdao 266071, Peoples R China 4.Lab Marine Geol, Qingdao Natl Lab Marine Sci & Technol, Qingdao 266061, Peoples R China 5.Univ Durham, Dept Earth Sci, Durham DH1 3LE, England
推荐引用方式 GB/T 7714	Xue, Song,Niu, Yaoling,Chen, Yanhong,et al. Iron Isotope Fractionation during Skarn Cu-Fe Mineralization[J]. MINERALS,2021,11(5):18.
APA	Xue, Song.,Niu, Yaoling.,Chen, Yanhong.,Shi, Yining.,Xia, Boyang.,...&Duan, Meng.(2021).Iron Isotope Fractionation during Skarn Cu-Fe Mineralization.MINERALS,11(5),18.
MLA	Xue, Song,et al."Iron Isotope Fractionation during Skarn Cu-Fe Mineralization".MINERALS 11.5(2021):18.