安徽庐枞盆地黄屯隐爆角砾岩筒型金铜矿床碲元素的分布、分配特征及沉淀机制研究  

Study of occurrence states and precipitation mechanism of tellurium in Huangtun Au-Cu-bearing breccia pipe in Luzong Basin,Anhui,eastern China

作　　者：王彪[1,2] 范裕 周涛发[1,2] 李飞 赵永建[3] 钟镇海 刘冠宇 高轩昊 WANG Biao;FAN Yu;ZHOU TaoFa;LI Fei;ZHAO YongJian;ZHONG ZhenHai;LIU GuanYu;GAO XuanHao(School of Resources and Environmental Engineering,Ore Deposit and Exploration Centre(ODEC),Hefei University of Technology,Hefei 230009,China;Anhui Province Engineering Research Center for Mineral Resources and Mine Environments,Hefei 23009,China;Anhui Province Jinding Mining Co.,Ltd.,Hefei 230009,China)

机构地区：[1]合肥工业大学资源与环境工程学院,合肥工业大学矿床成因与勘察技术研究中心,合肥230009 [2]安徽省矿产资源与矿山环境工程技术研究中心,合肥230009 [3]安徽省金鼎矿业股份有限公司,合肥230009

出　　处：《岩石学报》2023年第10期3048-3068,共21页Acta Petrologica Sinica

基　　金：国家自然科学基金项目(42072090、91962218);重点研发计划项目(2022YFC2903503);中央高校基本科研业务费专项(JZ2023HGQB0153)联合资助.

摘　　要：隐爆角砾岩筒型金(铜)矿床作为重要的金矿床类型,常伴生关键金属碲的矿化,然而对于此类矿床中碲的分布、分配特征及沉淀机制研究仍较为薄弱。黄屯矿床是长江中下游成矿带近年来发现的最为典型的隐爆角砾岩筒型金铜矿床,伴生有大量的碲化物产出。本文在详细的野外地质工作和岩相学观察基础上,发现碲在矿床中发生了显著富集。通过对黄屯矿床不同蚀变类型矿石及主要富碲矿物开展全岩及微区地球化学分析,明确了碲的分布、分配特征以及初步讨论了碲的沉淀机制。黄屯矿床成矿阶段从早到晚可划分为钠钙硅酸盐、钾硅酸盐、绿泥石-碳酸盐和伊利石-蒙脱石阶段,在不同深度形成了相应的蚀变带,并发育有不同强度的金铜矿化。黄屯矿床伴生的碲储量约有118.71t,平均品位为5.3g/t,达到中型规模,具备重要的综合利用价值。钾硅酸盐蚀变带碲的分布比例最高,占总储量约92.37%,平均品位约为9.6g/t。钾硅酸盐蚀变带内约有89%~99%的碲呈独立矿物,主要以微米级、纳米级的碲铋矿包体的形式分布在黄铁矿中,剩余部分则以类质同象的形式赋存在黄铁矿和黄铜矿内。减压沸腾引起流体温度骤降导致硫化物沉淀,和沸腾过程中释放大量气相H_(2)S,共同导致流体的f(Te_(2))/f(S_(2))比值升高,可能是黄屯矿床中碲沉淀富集的主要机制。The breccia pipe-hosted gold(copper)deposits are an important type of gold deposits,which are often accompanied by the critical metal tellurium mineralization.However,studies on the distribution and allocational characteristics and the precipitation mechanism of the tellurium in this type deposit are still weak.The Huangtun deposit is the most typical breccia pipe-hosted gold-copper deposit discovered in the Middle-Lower Yangtze River Valley Metallogenic Belt in recent years,accompanied by a large amount of telluride.Based on detailed field geological work and petrographic observations,this paper discovers a significant enrichment of tellurium in the deposit.Through whole-rock and micro-area geochemical analyses on different alteration types of ore and main tellurium-rich minerals in the Huangtun deposit,the distribution and allocation characteristics of the tellurium were clarified,and the precipitation mechanism of the tellurium was preliminarily discussed.The mineralization stages of the Huangtun deposit can be divided from early to late into sodium-calcium silicate,potassium silicate,chlorite-carbonate and illite-montmorillonite stages,forming corresponding alteration zones at different depths,and developing different intensities of gold and copper mineralization.The accompanying tellurium reserves of the Huangtun deposit are about 118.71t,with an average grade of 5.3g/t,reaching a medium scale and possessing significant integrated utilization value.Among them,potassium silicate altered ore is the main tellurium-rich ore,accounting for about 92.37% of the total reserves with an average grade of about 9.6g/t.About 89% to 99% of the tellurium in potassium silicate altered ore exists as independent minerals,mainly micron-sized and nano-sized tellurobismuthite inclusions distributed in pyrite,and the remaining part is in the form of isomorphs in pyrite and chalcopyrite.The sharp drop of the fluid temperature caused by decompression boiling leads to the sulfide precipitation,while the boiling process releases a la

关 键 词：隐爆角砾岩筒 黄屯金铜矿床 碲 赋存状态 沉淀机制 

分 类 号：P618.41[天文地球—矿床学] P618.83[天文地球—地质学]