金顶铅-锌-镉-铊矿床稀散元素Cd的赋存状态及矿床成因  

Occurrence of rare-dispersed element Cd in the Jinding lead-zinc-cadmiumthallium deposit,and its ore genesis

作　　者：胡蓉 段泓羽 杨献珍 杨立飞 李峤昕 王长明[1,2] HU Rong;DUAN Hongyu;YANG Xianzhen;YANG Lifei;LI Qiaoxin;WANG Changming(College of Earth Science and Resource,China University of Geosciences(Beijing),Beijing 100083,China;China State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Beijing 100083,China;China Yunnan Jinding Zn Industry Company,Ltd.,Nujiang 673100,Yunnan,China;China College of Earth Sciences,East China University of Technology,Nanchang 330213,Jiangxi,China)

机构地区：[1]中国地质大学(北京)地球科学与资源学院,北京100083 [2]中国地质大学地质过程与矿产资源国家重点实验室,北京100083 [3]云南金鼎锌业有限公司,云南怒江673100 [4]东华理工大学地球科学学院,江西南昌330013

出　　处：《矿产勘查》2023年第8期1350-1366,共17页Mineral Exploration

基　　金：国家基金委重大研究计划(92162101);国家科技部重点研发计划项目(2020YFA0714802)联合资助。

摘　　要：云南金顶铅-锌-镉-铊矿床是世界级超大型矿床。本文利用TIMA对金顶矿床原生矿石锌/铅/硫精粉中Cd元素的赋存状态开展系统研究,并对黄铁矿和闪锌矿开展原位LA-ICP-MS微量元素分析。结果显示,闪锌矿中稀散元素Cd的含量为519.80×10^(-6)~116155.00×10^(-6),锌精粉中富镉区域广泛分布体积分数极低的硫镉矿。稀散元素Cd主要是以类质同象的形式赋存于闪锌矿晶格内,极少数是以镉的独立硫化物形式产出。闪锌矿以富含Cd、Pb、Cu元素,贫Fe、Mn、In等元素为特征,具有较低的In/Ge、In/Ga比值(平均值分别为0.008和0.014);黄铁矿中的Co、Ni元素含量较低,Co/Ni比值(平均值为1.766)指示黄铁矿具有沉积成因和热液成因。这些特征均表明该矿床主要形成于中低温环境。综合矿床地质特征和硫化物微量元素特点,认为金顶矿床属于密西西比河谷型(MVT)铅锌矿床。The Jinding Pb-Zn-Cd-Tl deposit is a world-class super-large deposit in Yunnan Province.The occurrence of cadmium in zinc/lead/sulfur concentrate of primary ore of the Jinding deposit was systematically studied by TIMA,and the pyrite and sphalerite of the deposit were analyzed by LA-ICP-MS.The results show that the rare-dispersed metal Cd content in sphalerite is 519.80×10^(-6)-116155.00×10^(-6),and greenockite with very low volume fraction is widely distributed in the cadmium-rich area of zinc concentrate powder.The rare-dispersed metal cadmium mainly exists as isomorphism in sphalerite lattice,and little exists as independent sulfide mineral of cadmium.Sphalerite is rich in Cd,Pb and Cu and poor in Fe,Mn and In,with low In/Ge and In/Ga ratios(mean 0.008 and 0.014,respectively).The content of Co and Ni in pyrite is low,and the Co/Ni ratio(mean 1.766)indicates that pyrite has sedimentary and hydrothermal origin.All these characteristics indicate that the deposit was mainly formed in a medium and low temperature metallogenic environment.Based on the geological characteristics of the deposit and trace element features of sulfides,the Jinding deposit is considered a Mississippi Valley-type(MVT)lead-zinc deposit.

关 键 词：稀散金属 镉元素 赋存状态 矿床成因 金顶矿床 

分 类 号：P618.81[天文地球—矿床学]