大兴安岭北段古利库金(银)矿床流体包裹体特征与成矿机制  

Fluid Inclusions and Metallogenic Mechanism of Guliku Au-Ag Deposit in Northern Daxinganling

作　　者：李春诚[1,2,3,4] 吕新彪[2,3] 杨永胜[4] 高荣臻[5] 

机构地区：[1]湖北省地质科学研究院,武汉430034 [2]中国地质大学(武汉)资源学院,武汉430074 [3]中国地质大学(武汉)地质过程与矿产资源国家重点实验室,武汉430074 [4]中国地质大学(武汉)地质调查研究院,武汉430074 [5]中国地质大学(北京)地球科学与资源学院,北京100083

出　　处：《地质科技情报》2016年第2期152-160,共9页Geological Science and Technology Information

基　　金：中国地质调查局项目:内蒙古自治区莫力达瓦达翰尔族自治旗拉抛等八幅1:5万区域矿产地质调查项目(NMKD2010-3);内蒙古自治区呼伦贝尔市营林区等二幅1:5万区域矿产地质调查项目(NMKD2014-23)

摘　　要：古利库金（银）矿床位于中生代大杨树火山断陷盆地北东缘与新元古代-早寒武世落马湖隆起的接壤部位。矿体主要赋存于下白垩统龙江组火山岩及其与新元古界-下寒武统落马湖群变质岩接触带附近,严格受古火山机构及其外围的环形断裂控制。热液成矿阶段分为早期石英阶段、玉髓-黄铁矿阶段、石英-黄铁矿阶段、石英-多金属硫化物阶段、石英-碳酸盐阶段。对古利库矿床进行的系统岩相学和流体包裹体研究表明,流体包裹体类型为富液相包裹体、富气相包裹体和纯气相包裹体,以富液相包裹体为主。成矿温度为136~367℃,从成矿早期至晚期分别为270~367,255~304,179~318,136~279℃。盐度w（NaCleqv）为1.4%~8.0%,成矿深度为1.0km,成矿流体以大气降水为主,显示低硫型浅成低温热液金矿成矿特征。含矿石英脉中广泛发育冰长石和叶片状方解石-石英,结合流体包裹体特征表明,流体的沸腾作用是引起成矿流体中矿质发生沉淀富集的主要成矿机制。The Guliku Au-Ag deposit is located at the connection Mesozoic Dayangshu volcanic fault basin and Neoproterozoic-Early Cambrian Luomahu intermediate uplift on the margin of Daxinganling volcanic belt.Ore bodies are hosted in Lower Cretaceous Longjiang Formation volcanic rocks and its contact zone with Neoproterozoic-Early Cambrian Luomahu Group metamorphic rock,which are strictly controlled by the circular faults of palaeocaldera margin.The mineralization can be divided into five main stages：quartz vein stage,chalcedony-pyrite vein stage,quartz-pyrite vein stage,quartz-polymetallic sulfide vein stage and quartz-carbonate vein stage.Three types of fluid inclusions formed in major mineralization stages were recognized：I liquid-rich two phase fluid inclusion;II gas-rich fluid inclusion and III pure gaseous inclusions,with the former one predominating.The ore forming temperature ranges from 136℃to 367℃,with the homogenization temperatures of the metallogenic stages being 270-367℃,255-304℃,179-318℃and 136-279℃ respectively.The ice melting temperatures of fluid inclusions range from-0.8℃ to5.1℃,and the corresponding salinities are 1.4%-8.0% NaC1 eq.Based on the salinities and homogenization temperatures,we suggest the ore-forming depth is 1.0km.Ore fluids,coming mainly from circulating meteoric water,are low-sulfidation epithermal fluid characteristic respectively.Appearance of adularias,bladed calcite-quartz and coexisting type I,typeⅡ and typeⅢinclusions suggests that boiling is the main factor for the deposition of ore solutes.

关 键 词：古利库金(银)矿床 低硫型 成矿流体 沸腾作用 

分 类 号：P618.51[天文地球—矿床学]