广西佛子冲铅锌矿田闪锌矿LA-ICP-MS微量元素特征及指示意义  

LA-ICP-MS analysis of trace element characteristics and geological implications in sphalerites from Fozichong lead zinc ore field,Guangxi Autonomous Region,China

作　　者：常晋阳 吴小雷 王加昇[3] 曾南石 姜海 范春宝 黄长帅 李敏 赵毅 CHANG Jinyang;WU Xiaolei;WANG Jiasheng;ZENG Nanshi;JIANG Hai;FAN Chunbao;HUANG Changshuai;LI Min;ZHAO Yi(Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration,Giuilin University of Techmology,Giuilin Giuangxi Zhuang Autonomous Region 541004,China;China Nonferrous Metals(Guilin)Geology and Mining Co,Ltd,Giuilin Guangxi Zhuang Autonomous Region 541004,China;Southwest Institute of Geological Survey,Kunming University of Science and Technology,Kunming Yunnan 650093,China;Chifeng NFC Baiyinnuoer Mining Co.,Ltd.,Chifeng Inner Mongolia Autonomous Region 024005,China)

机构地区：[1]桂林理工大学地球科学学院广西隐伏金属矿产勘查重点实验室,广西壮族自治区桂林541004 [2]中国有色桂林矿产地质研究院有限公司,广西壮族自治区桂林541004 [3]昆明理工大学国土资源工程学院西南地质调查所,云南昆明650093 [4]赤峰中色白音诺尔矿业有限公司,内蒙古自治区赤峰024005

出　　处：《矿物学报》2024年第3期335-349,共15页Acta Mineralogica Sinica

基　　金：广西隐伏金属矿产勘查重点实验室开放课题(编号:20-065-17-K03);“十二五”国家科技支撑计划项目(编号:2015BAB05B00);中国有色集团科技计划项目(编号:2020KJH1);中色桂林院创新基金(编号:KDY2019003)。

摘　　要：广西佛子冲铅锌矿田所在的钦杭成矿带西段是广西重要的多金属矿集区,矿田范围内发现的铅锌矿有条带状、浸染状、热液脉状3种类型矿石。3种类型矿石中的闪锌矿均具有Fe元素最为富集,Cd元素富集,Co元素较富集,In元素亏损,Ge、As、Mo、Tl元素含量低且含量变化不大的特征,但三者Fe元素含量存在一定差异,条带状闪锌矿w(Fe)<浸染状闪锌矿w(Fe)<热液脉状闪锌矿w(Fe)。3种闪锌矿的Mn、Fe、Co、Cd、In元素以类质同象的形式赋存于闪锌矿的晶格中,Cu、Pb、Bi元素则以独立矿物(黄铜矿、方铅矿、辉铋矿)或显微包裹体的形式赋存于闪锌矿中,但3种闪锌矿的Ag元素的赋存形式却存在一定差异。其中,条带状与热液脉状闪锌矿的Ag元素主要以独立矿物(自然银)或显微包裹体的形式赋存于闪锌矿之中,而浸染状闪锌矿的Ag元素则可能以类质同象的形式赋存于闪锌矿的晶格中。3种闪锌矿中Fe对Cd(或Mn、Co、In)与Zn的替代所起到的作用存在一定差异,其中条带状闪锌矿中Fe对Cd(或Mn)与Zn的替代可能起一定促进作用,对Co(或In)与Zn的替代机制所起作用不明。浸染状闪锌矿中Fe对Cd(或Mn、Co、In)与Zn的替代均起促进作用。而热液脉状闪锌矿中Fe对Mn与Zn的替代起促进作用,对Cd(或In)与Zn的替代可能也起到一定促进作用,但却对Co与Zn的替代起到了抑制进作用。3种闪锌矿的形成与岩浆活动密切相关,但沉积改造作用在条带状闪锌矿的形成过程中也发挥了重要作用。条带状闪锌矿可能形成于中-低温环境,浸染状和热液脉状闪锌矿则可能形成于中-高温环境,但热液脉状闪锌矿形成温度可能高于浸染状闪锌矿。结合Ga/Ge-Zn/Cd和Zn/Cd-Mn投影及前人的研究成果综合分析认为佛子冲铅锌矿田存在喷流沉积型、矽卡岩型、岩浆热液型3种矿床成因类型。The western part of Qinhang metallogenic belt where the Fozichong Pb-Zn ore field is located is an important polymetallic ore concentration area in Guangxi Zhuang Autonomous Region.The Pb-Zn ore deposits found in the orefield have banded,disseminated and hydrothermal veined ores.Among these three types of ores,sphalerite is characterized with the most enriched Fe element,enriched Cd element,relatively enriched Co element,depleted in element,and little changed low contents of Ge,As,Mo.However,there are some differences in Fe contents of sphalerites among the three types of ores,with w(Fe)of the banded sphalerite<that of the disseminated sphalerite<that of the hydrothermal vein sphalerite.The elements of Mn,Fe,Co,Cd,and In occurred in the lattice of three types of sphalerites in the form of isomorphism,while the elements of Cu,Pb,and Bi occurred in the form of independent minerals(chalcopyrite,galena,bismuthite)or micron inclusions in sphalerites.However,Ag occurred in different forms in three types of sphalerites.Especially,Ag occurred mainly in forms of independent mineral(natural silver)or micron inclusion in sphalerites of banded and hydrothermal veined ores,while it could occur in form of isomorphism in the lattice of sphalerite of the disseminated ore.There are some differences in the roles of Fe for substituting Cd(or Mn,Co,In)and Zn in the three types of sphalerites.Fe in the sphalerite of banded ore may play a certain role for promoting the substitution of Zn by Cd(or Mn),but its role in the substitution mechanism of Zn by Co(or In)is unknown.Fe In disseminated sphalerite promotes the substitution of Cd(or Mn,Co,In)and Zn.In the sphalerite of hydrothermal veined ore,Fe promoted the substitution of Zn by Cd(or Mn,Co,In)and Zn.However,in the sphalerite of hydrothermal veined ore,Fe promoted the substitution of Zn by Mn,the substitution of Zn by Cd(or In)to some extent,but inhibited the substitution of Zn by Co.The formation of three types of sphalerites is closely related to the magmatic activity.However,the

关 键 词：闪锌矿 微量元素 佛子冲铅锌矿田 LA-ICP-MS 成因类型 

分 类 号：P595[天文地球—地球化学] P571[天文地球—地质学]