矿床地质2023，Vol.42Issue(6)：1195-1213,19.DOI:10.16111/j.0258-7106.2023.06.007
内蒙古复兴屯超大型银铅锌矿床成因:闪锌矿微量元素组成的制约
Genesis of Fuxingtun super large Ag-Pb-Zn deposit,Inner Mongolia:Constraints on the trace elements composition of sphalerite
摘要
Abstract
The Fuxingtun deposit,located in the southern Great Xing'an Range,is a newly discovered giant Ag-Pb-Zn deposit dominated by Ag.The deposit,hosted in the early Cretaceous volcanic rocks and pyroclastic rocks,is characterized by the occurrence of(Fe-poor)sphalerite,chalcopyrite,galena,and tetrahedrite/tennantite associa-tions.Carbonate,kaolinization,and pyrophyllitization are the most common wall rock alteration in this deposit.The ore-forming process of this deposit can be divided into three stages:Cu-Zn sulfide stage(stage Ⅰ),Pb-Zn sulfide stage(stage Ⅱ),and Ag-Zn sulfide stage(stage Ⅲ).The composition and trace elements occurrence of sphalerite in this deposit were analyzed by LA-ICP-MS.The results show that the sphalerite in this deposit is characterized by enrichment of Cu,Ag,Pb and depletion in Fe,Cd,Ga and Ge.The Fe-poor sphalerite in the de-posit indicates that the Fuxingtun deposit was formed in a medium to low temperature environment.From the stagesⅠtoⅢ,Fe,Mn,and In in sphalerite gradually decreased,while the contents of Ga,Ge and Sb slightly in-creased,indicating that the temperature of ore-forming fluid gradually decreased.Ag and Cu can substitute Zn in the lattice of sphalerite,which may be an important possible factor for the enrichment of Ag in the sphalerite of this deposit.The oscillatory zoning of sphalerite reflects that the ore-forming fluid was in an oscillatory environ-ment during sphalerite formation.The phase separation of ore-forming fluids caused by multiple pressure fluctua-tions is an important mechanism of metallogenic material precipitation.The trace elements of sphalerite in this de-posit are similar to that of medium-low temperature magmatic-hydrothermal deposit and different from MVT,Sedex,VMS,Skarn,and medium-high temperature magmatic-hydrothermal deposits.Combined with the geologi-cal characteristics,we considered that the Fuxingtun Ag-Pb-Zn deposit belongs to the epithermal deposit.关键词
LA-ICP-MS/闪锌矿/微量元素/浅成低温热液矿床/复兴屯银铅锌矿床Key words
LA-ICP-MS/sphalerite/trace elements/epithermal deposit/Fuxingtun Ag-Pb-Zn deposit分类
天文与地球科学引用本文复制引用
陆泽芊,武广,陈公正,段海龙,杨艳霞,刘洪岩,李敏,钱军,李海军,梁新强..内蒙古复兴屯超大型银铅锌矿床成因:闪锌矿微量元素组成的制约[J].矿床地质,2023,42(6):1195-1213,19.基金项目
本文得到内蒙古自治区地质勘查基金项目(编号:18-1-KY02)、国家自然科学青年基金项目(编号:42202080)和内蒙古玉龙矿业股份有限公司科研项目(编号:2020110033002072)联合资助 （编号:18-1-KY02）
