摘要
浑江金矿是近年来在我国东北地区发现的重要微细浸染型金矿床。矿化严格受控于大横路断裂下盘富含有机质的碳酸盐岩地层。包裹体研究和热力学计算表明，成矿温度为１８２～２３０℃，压力为５．６６×１０７～６．１６×１０７Ｐａ，形成深度小于２．５ｋｍ。成矿流体具有中—弱碱性、强还原性等地下热卤水特征。元素地球化学研究证实含矿碳酸盐建造为金矿床的形成提供了物质基础。矿源层中的金以［Ａｕ（ＨＳ）２］－形式活化进入溶液，促使金沉淀富集的机制是溶液中还原硫活度降低。
The Hunjiang gold deposit is the first micro disseminated (Carlin type)one which was discovered in recent years in the north east China.The orebodies are confined in the Carbonate formation with rich organic matter distributed along the foot wall of the Dahenglu fault.Studies on fluid inclusion and thermodynamic calculations indicate that temperatures of ore formation were from 182℃ to 230℃,pressure,from 5.66×10 7 to 6. 16×10 7Pa,and depth, 2.5km .Ore forming solutions were neutral to weakly basic,relatively reductive and is of typical character of subterrane hot bittern.Geochemical studies on micro element show that Au,Pb,Zn,Sb and As contents of the carbonate formation.Proterozoic are obviously higher than their average value in the upper continental crust,and their coefficients of variation indicate they are activated,and suggest that the carbonate formation is ore bearing formation.It supplied mainly ore forming substances for Hunjiang gold deposits.The gold in source rocks was mobilized and entered the convecting meteoric water by the following chemical reaction and migrated as the hydro sulfide complex [Au(HS) 2] -.The effective mechanism for gold deposition is the decrease in reduced sulfur activity caused by deposition of sulfides such as pyrite and stibnite in hydrothermal ore solution,and the decline in O 2 fugacity as well as the reduction and the absorbtion of organic matter.
出处
《吉林地质》
1997年第1期42-50,共9页
Jilin Geology
关键词
金矿床
地质特征
矿床成因
成硫流体
Micro disseminated gold deposit Mineralizing fluid Physical chemical condition The genesis of ore deposit Hunjiang gold deposit
