(1. 中南大學(xué) 有色金屬成礦預(yù)測與地質(zhì)環(huán)境監(jiān)測教育部重點實驗室，長沙 410083； 2. 中南大學(xué) 地球科學(xué)與信息物理學(xué)院，長沙 410083； 3. 湖南華中礦業(yè)有限公司，長沙 410003)
摘 要: 根據(jù)脈體穿插關(guān)系和礦物組合特征，將李壩金礦床的成礦作用劃分為熱液期和表生期，其中熱液期又可劃分為黃鐵礦階段、黃鐵絹英巖階段和多金屬硫化物階段3個成礦階段。運用電子探針(EPMA)對3個成礦階段的主要金屬硫化物(黃鐵礦、毒砂、閃鋅礦)開展成分分析和Au賦存狀態(tài)分析。結(jié)果表明：李壩金礦床黃鐵礦w(Co)/w(Ni)比值(0.15~4.50)及閃鋅礦內(nèi)FeS分子數(shù)(18.81%~22.97%)指示該礦床形成于中高溫的物理化學(xué)環(huán)境。主要金屬硫化物含金量、黃鐵礦As-Au圖解及Au元素面掃描分析圖指示黃鐵礦和毒砂是李壩金礦床重要載金礦物，Au主要是以納米級顯微-超顯微自然金(Au0)的形式存在。綜合地質(zhì)特征及金屬硫化物的地球化學(xué)特征，推測李壩金礦床屬于與中川巖漿活動有關(guān)的中高溫中深成熱液金礦床。
關(guān)鍵字: 金屬硫化物；化學(xué)成分；電子探針；李壩金礦床
（1. Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geologicao Environment Monitor (Central South University), Ministry of Education, Changsha 410083, China; 2. School of Geoscience and Infophysics, Central South University, Changsha 410083, China; 3. Hunan Huazhong Mining Co., Ltd., Changsha 410083, China）
Abstract:Based on the ore veins intercalation and minerals association, the mineralization in Liba gold deposit can be divided into hydrothermal stage and exogenous stage. The hydrothermal stage consists of three phases, which are pyrite phase, beresite phase, and polymetallic phase. Component analysis and Au distribution states analysis of metal sulfides (pyrite, arsenopyrite, sphalerite) of three phases were carried out by means of electron probe microanalysis (EPMA). The results show that the w(Co)/w(Ni) ratio(0.15-4.50) of pyrite and FeS molecular number(18.81%-22.97%) in sphalerite indicate that the Liba gold deposit forms in the medium-high temperature environment. The Au content, As-Au relationship diagram and distribution analysis of Au element in metal sulfides indicate that pyrite and arsenopyrite are the main gold-bearing minerals in Liba gold deposit, besides micro and sub-micro native gold inclusion are the dominant occurrence in pyrite and arsenopyrite. Based on the geological characteristics and the component characteristic of metal sulfides, Liba gold deposit is regarded as a medium-high temperature and medium-deep hydrothermal gold deposit which is closely related to Zhongchuan instructive.
Key words: metal sulfides; component; EPMA; Liba gold deposit
