河南熊耳山东草沟金矿石英流体包裹体研究  

Study on Fluid Inclusion of Puartz from the Dongcaogou Gold Deposit,Xiong′ershan region,Henan Province

作　　者：陈坤 CHEN Kun(MOE Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring,Changsha,410083,P.R.China;School of Geosciences and Info-physics,Central South University,Changsha,410083,P.R.China)

机构地区：[1]中南大学地球科学与信息物理学院,湖南长沙410083 [2]中南大学有色金属成矿预测与地质环境监测教育部重点实验室,湖南长沙410083

出　　处：《南方金属》2023年第5期7-10,22,共5页Southern Metals

摘　　要：为揭示熊耳山东草沟金矿床成矿流体性质和流体演化过程,以与金矿关系密切的石英为研究对象,开展了系统的野外调查以及流体包裹体岩相学和显微测温研究。结果表明,东草沟金矿体分布主要受构造控制,成矿期次可分为3个阶段:早期石英+绢云母+黄铁矿阶段、中期石英+多金属硫化物阶段、晚期石英+碳酸盐岩。主要存在5种类型的流体包裹体:D型,含子矿物包裹体;C型,含CO 2水溶液包裹体;LV型,气液两相包裹体;L型,单水溶液包裹体;V型,单水蒸气相包裹体。根据升温过程中子矿物与气泡消失的先后情况,D型包裹体可进一步分为Da型(子矿物先消失)和Db型(气泡先消失)。Da型包裹体子矿物融化温度为211~240℃,均一温度为216~391℃,盐度值32.4%~34.1%;Db型气液相均一温度为172~267℃,盐度值为30.6%~35.8%。C型包裹体笼合物融化温度为-1.9~8.7℃,盐度为2.6%~17.3%,均一温度为276~310℃。LV型包裹体在第1阶段、2a阶段、2b阶段、3阶段LV型均质温度分别为138~310℃、148~403℃、130~255℃、113~199℃;盐度为1.2~11.5 w t%,2.1~21.7 wt%,1.6~15.3 w t%,10.6~15.3 w t%,0.2~13.2 w t%。分析认为,矿区存在不同性质的成矿流体,且初始流体为岩浆热液系统,后期流体不断演化,流体不混溶是金沉淀的主要诱因,而流体混合则导致了银铅锌等的沉淀。In order to reveal the ore-forming fluid properties and fluid evolution process of Dongcaogou gold deposit in Xiong’ershan region,systematic field investigation,fluid inclusion petrography and microthermometry of gold related quartz were studied.The distribution of Dongcaogou gold orebody is mainly controlled by the structure.The three-stage hydrothermal events have been identified:early quartz+sericite+pyrite stage(stage 1),then quartz+polymetallic sulfides stage(stage 2),and then late quartz-carbonate vein stage(stage 3).Five types of inclusions can be distinguished in the Dongcaogou Au deposit:Types D,C,LV,L and V.Type D are further subdivided into Da-type and Db-type based on dissolution of daughter minerals before or after the absent of the gas bubbles during the heating processes.The inclusions Da-type show halite dissolution temperatures of 211~240℃,which are corresponded to NaCl equivalent salinities of 32.4~34.1 wt%,while the homogenization temperature are 216~391℃.The inclusions Db-type have halite dissolution temperatures of 172~267℃,which are corresponded to NaCl equivalent salinities of 30.6~35.8 wt%.In the inclusions Type C,Tm-clath values ranges-1.9℃to 8.7℃,while the calculated salinities varies from 2.6 to 17.3 wt%.The Th-tot values varies from 276 to 310℃.Homogenization temperatures of Type LV in stage 1,2a,2b and 3 are 138~310℃,148~403℃,130-255℃,113~199℃respectively,corresponding to salinities of 1.2~11.5 wt%,2.1~21.7 wt%,1.6~15.3 wt%,10.6~15.3 wt%,0.2~13.2 wt%.Different properties of ore-forming fluids have been identified,and the initial fluid may be magmatic hydrothermal system.Fluid miscibility is the main cause of gold precipitation,and fluid mixing leads to the precipitation of silver,lead and zinc.

关 键 词：流体包裹体 成矿流体 东草沟 金矿床 

分 类 号：P618.2[天文地球—矿床学]