摘要
二道坎银矿床是大兴安岭东北部首次发现的三叠纪大型银矿床。矿体位于上志留统—中泥盆统泥鳅河组沉积岩中,辉绿岩脉与矿体密切共生。矿石为石英脉胶结的构造角砾岩,目前以地表氧化矿石为主。矿石中金属矿物主要为黄铁矿、方铅矿,其次为闪锌矿、黄铜矿、黝铜矿、赤铁矿、磁铁矿等,含银矿物主要为辉银矿和硫锑银矿。矿石结构主要为粒状结构和固溶体分离结构,构造有致密块状、脉状-网脉状、角砾状和条带状构造等。成矿阶段主要为沥青-黄铁矿-石英阶段、石英-含银多金属硫化物阶段和石英-方解石阶段。矿区蚀变类型有硅化、绿泥石化、绢云母化、绿帘石化、碳酸盐化和赤铁矿化。综合分析认为二道坎银矿床为晚三叠世形成的浅成低温热液型银矿床。
Erdaokan Ag deposit is a large-scale Triassic Ag deposit which is firstly discovered in the northeast of Da Hinggan Mountains.The orebody is mainly hosted in the sedimentary rocks of Niqiuhe Formation of Upper Silurian System-Middle Devonian System.There is a closely symbiotic relationship between the diabase veins and orebodies.The ore is mainly composed of quartz-vein-cemented structural breccia,which is dominated by surface oxidized ore.The metal minerals in the ore are mainly pyrite and galena,secondly sphalerite,chalcopyrite,tetrahedrite,hemite,magnetite and so on.The silver-bearing minerals are mainly argentite and acrosite.The ore texture is mainly granular and solid solution separation texture,and the ore structure is dense and massive,vein-net vein,breccia and striped structure.The metallogenic stage is mainly divided into bitumen-pyrite-quartz stage,quartz-silver-bearing polymetallic sulfide stage and quartz-calcite stage.Hydrothermal alteration types are mainly silicification,chloritization,sericitization,epidotization,carbonatation,and hematization in the mining area.The result of comprehensive study shows that the Erdaokan Ag deposit belongs to an epithermal type formed during the Triassic period.
作者
徐文喜
李成禄
鲍希波
袁茂文
邓昌州
杨元江
徐国战
XU Wenxi;LI Chenglu;BAO Xibao;YUAN Maowen;DENG Changzhou;YANG Yuanjiang;XU Guozhan(Heilongjiang Institute of Geological Survey,Harbin 150036,Heilongjiang,China;China University of Geosciences,Beijing 100083,China)
出处
《矿产与地质》
2019年第3期434-441,共8页
Mineral Resources and Geology
基金
黑龙江省国土资源科研项目(黑国土科研201603)
国家自然科学基金(编号:41872038)共同资助
关键词
二道坎银矿床
三叠纪
地质特征
矿床成因
大兴安岭
Erdaokan silver deposit
Triassic period
geological characteristics
deposit genesis
Da Hinggan Mountains
