The occurrence and enrichment of cobalt in skarn Pb-Zn deposits: A case study of the Niukutou Co-rich deposit, East Kunlun metallogenic belt, western China

IF 3.2 2区 地球科学 Q1 GEOLOGY
Yu-Ying Che , Hui-Min Su , Tong Liu , Hua Li , Shu-Yue He
{"title":"The occurrence and enrichment of cobalt in skarn Pb-Zn deposits: A case study of the Niukutou Co-rich deposit, East Kunlun metallogenic belt, western China","authors":"Yu-Ying Che ,&nbsp;Hui-Min Su ,&nbsp;Tong Liu ,&nbsp;Hua Li ,&nbsp;Shu-Yue He","doi":"10.1016/j.oregeorev.2024.106210","DOIUrl":null,"url":null,"abstract":"<div><p>The East Kunlun orogenic belt is one of the most important Co-rich polymetallic metallogenic belts in China. Niukutou, a typical Pb-Zn-(Fe) skarn deposit, is situated within the marble formations of the Ordovician-Silurian Qimantagh Group in this belt. Six distinct stages of mineralization have been identified: (1) prograde skarn stage, (2) hydrous mineral-oxide stage, (3) pyrrhotite stage, (4) chalcopyrite stage, (5) sphalerite-galena stage, and (6) carbonate stage. Co enrichment predominantly manifests at chalcopyrite stage, with two distinct Co minerals identified: glaucodot and cobaltite. Co is also present as isomorphous substitution in sulfides (mostly arsenopyrite) and as inclusions in chalcopyrite. Variations in As and S contents in arsenopyrite suggest a steady decrease in ore-forming fluid temperature from the pyrrhotite stage to sphalerite-galena stage. Variations in the Co, Ni, Se, As, Sb, Cu, Sn, Ag, and Zn contents in pyrite indicate fluctuations in temperature, oxygen fugacity, and fluid composition during ore formation. Sulfur isotope compositions (δ<sup>34</sup>S) through the pyrrhotite stage to the sphalerite-galena stages show a limited range from +3.4 to +7.0 ‰, suggesting a predominantly magmatic source. Whereas, the δ<sup>34</sup>S of pyrite and marcasite in carbonate stage exhibit significant variations from −22.5 to +22.7 ‰. We propose that this significant variation may be caused by mixing of sulfur from the surrounding rocks and the large fluctuations in oxygen fugacity due to the influx of meteoric water at the carbonate stage. Overall, Co in Pb-Zn skarn system may occur either as independent minerals or as lattice substitution in sulfides such as arsenopyrite. The deposition of Co-bearing minerals is related to decreases in temperature and <em>f</em>O<sub>2</sub> during the chalcopyrite stage.</p></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":null,"pages":null},"PeriodicalIF":3.2000,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0169136824003433/pdfft?md5=47afabf606f049637756d17d7480b699&pid=1-s2.0-S0169136824003433-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Ore Geology Reviews","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0169136824003433","RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"GEOLOGY","Score":null,"Total":0}
引用次数: 0

Abstract

The East Kunlun orogenic belt is one of the most important Co-rich polymetallic metallogenic belts in China. Niukutou, a typical Pb-Zn-(Fe) skarn deposit, is situated within the marble formations of the Ordovician-Silurian Qimantagh Group in this belt. Six distinct stages of mineralization have been identified: (1) prograde skarn stage, (2) hydrous mineral-oxide stage, (3) pyrrhotite stage, (4) chalcopyrite stage, (5) sphalerite-galena stage, and (6) carbonate stage. Co enrichment predominantly manifests at chalcopyrite stage, with two distinct Co minerals identified: glaucodot and cobaltite. Co is also present as isomorphous substitution in sulfides (mostly arsenopyrite) and as inclusions in chalcopyrite. Variations in As and S contents in arsenopyrite suggest a steady decrease in ore-forming fluid temperature from the pyrrhotite stage to sphalerite-galena stage. Variations in the Co, Ni, Se, As, Sb, Cu, Sn, Ag, and Zn contents in pyrite indicate fluctuations in temperature, oxygen fugacity, and fluid composition during ore formation. Sulfur isotope compositions (δ34S) through the pyrrhotite stage to the sphalerite-galena stages show a limited range from +3.4 to +7.0 ‰, suggesting a predominantly magmatic source. Whereas, the δ34S of pyrite and marcasite in carbonate stage exhibit significant variations from −22.5 to +22.7 ‰. We propose that this significant variation may be caused by mixing of sulfur from the surrounding rocks and the large fluctuations in oxygen fugacity due to the influx of meteoric water at the carbonate stage. Overall, Co in Pb-Zn skarn system may occur either as independent minerals or as lattice substitution in sulfides such as arsenopyrite. The deposition of Co-bearing minerals is related to decreases in temperature and fO2 during the chalcopyrite stage.

Abstract Image

矽卡岩铅锌矿床中钴的出现和富集:中国西部东昆仑成矿带牛角头富钴矿床案例研究
东昆仑造山带是中国最重要的富钴多金属成矿带之一。典型的铅锌(铁)矽卡岩矿床牛角头位于该带奥陶系-志留系祁漫塔组大理岩层中。已确定矿化分为六个不同阶段:(1)原生矽卡岩阶段;(2)含水矿物-氧化物阶段;(3)黄铁矿阶段;(4)黄铜矿阶段;(5)闪锌矿-方铅矿阶段;(6)碳酸盐阶段。钴富集主要表现在黄铜矿阶段,发现了两种不同的钴矿物:釉钴和钴铁矿。钴还以同素异形替代物的形式存在于硫化物(主要是砷黄铁矿)和黄铜矿的包裹体中。砷黄铁矿中 As 和 S 含量的变化表明,从黄铁矿阶段到闪锌矿-方铅矿阶段,成矿流体温度持续下降。黄铁矿中 Co、Ni、Se、As、Sb、Cu、Sn、Ag 和 Zn 含量的变化表明,在矿石形成过程中,温度、氧富集度和流体成分会发生波动。从黄铁矿阶段到闪锌矿-方铅矿阶段的硫同位素组成(δ34S)显示出从 +3.4 到 +7.0 ‰ 的有限范围,表明主要来源于岩浆。而碳酸盐阶段黄铁矿和黑云母的δ34S则在-22.5至+22.7 ‰之间呈现显著变化。我们认为,这种显著的变化可能是由于围岩中硫的混入以及碳酸盐阶段流星水的涌入导致氧富集度的大幅波动造成的。总体而言,铅锌矽卡岩系统中的钴可能以独立矿物的形式存在,也可能以晶格置换的形式存在于砷黄铁矿等硫化物中。含钴矿物的沉积与黄铜矿阶段温度和 fO2 的降低有关。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
Ore Geology Reviews
Ore Geology Reviews 地学-地质学
CiteScore
6.50
自引率
27.30%
发文量
546
审稿时长
22.9 weeks
期刊介绍: Ore Geology Reviews aims to familiarize all earth scientists with recent advances in a number of interconnected disciplines related to the study of, and search for, ore deposits. The reviews range from brief to longer contributions, but the journal preferentially publishes manuscripts that fill the niche between the commonly shorter journal articles and the comprehensive book coverages, and thus has a special appeal to many authors and readers.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信