滇西北羊拉大型铜矿床构造热液成矿作用的流体包裹体证据  

Tectonic Hydrothermal Metallogenesis in the Yangla Cu Deposit,Nouthwest Yunnan Province: Evidence from Fluid Inclusions

作　　者：李波[1] 丁俊英[2] 黄智龙[3] 周家喜[3] 刘月东 杜丽娟 LI Bo;DING Junying;HUANG Zhilong;ZHOU Jiaxi;LIU Yuedong;DU Lijuan(Southwest Institute of Geological Survey, Geological Survey Centre for Nonferrous Metals Resources, Facuhy of Land Resources Engineering, Kunming University of Science and Technology, Kunming 650093, China;National Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210093, China;National Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China;Yunnan Diqing Mining Co. Ltd. , Shangrila, Yunnan 674400, China)

机构地区：[1]昆明理工大学国土资源工程学院有色地质调查中心西南地质调查所,云南昆明650093 [2]南京大学内生金属矿床成矿机制研究国家重点实验室,江苏南京210093 [3]中国科学院地球化学研究所矿床地球化学国家重点实验室,贵州贵阳550002 [4]云南迪庆矿业开发有限责任公司,云南香格里拉674400

出　　处：《昆明理工大学学报（自然科学版）》2018年第3期25-36,共12页Journal of Kunming University of Science and Technology(Natural Science)

基　　金：国家自然科学基金项目(41402072);云铜集团重点科技项目(20110103);昆明理工大学重点学科建设基金项目(14078384);昆明理工大学分析测试基金项目(2017M20162101054)

摘　　要：滇西北羊拉大型铜矿床为金沙江成矿带内的代表性铜矿床,目前地质证据显示其在矽卡岩主成矿期之后,经历了构造热液成矿作用.为了研究羊拉铜矿床构造热液成矿作用的流体特征,本文选择该成矿期矿石中的方解石和石英系统开展了流体包裹体岩相学、显微测温及激光拉曼光谱采集等测试工作.研究结果表明:构造热液期方解石中流体包裹体类型主要为富液相气液两相(L+V)包裹体和纯液相(L)包裹体,石英中的流体包裹体则主要为富液相气液两相(L+V)包裹体、富气相气液两相(L+V)包裹体、纯气相(V)包裹体、纯液相(L)包裹体和含子矿物三相(L+V+S)包裹体.方解石中的流体包裹体均一温度集中于143~201℃之间,平均为169.9℃;石英中的流体包裹体均一温度在138~322℃之间,峰值区间为160~220℃;热液流体主要为中温、中-低温流体,明显低于羊拉铜矿床矽卡岩成矿期的流体温度.方解石中的流体包裹体盐度在1.40%~17.96%NaCl之间,平均值为10.07%NaCl;石英中的流体包裹体盐度在0.18%~17.08%NaCl之间,平均为6.12%NaCl;亦明显低于矽卡岩成矿期的流体盐度.构造热液期的流体包裹体总体表现为中-低温、中-低盐度,其成分主要为CH_4和H_2O,其次为N_2和CO_2,明显有别于羊拉铜矿床的矽卡岩成矿期的流体性质.The Yangla deposit is the most representative Cu deposit in the Jinshajiang metallogenic belt. Geological evidence has shown that tectonic hydrothermal mineralization also contributed to the formation of the Yangla after the skarn-type mineralization. In this paper,fluid inclusion petrography,microthermometric measurements and Laser Raman microspectroscopy for calcite and quartz from tectonic hydrothermal ore stage are utilized to study the nature of tectonic ore fluids. The results show that the fluid inclusions in calcite are mainly two-phase,liquid-rich（L ＋ V） type and pure liquid（L） type,their homogenization temperatures range from 143 to 201 ℃（average： 169. 9 ℃）,with corresponding salinities of 1. 40% - 17. 96% NaCl（average： 10. 07%NaCl）. Whilst,the fluid inclusions in quartz are two-phase,liquid-rich（L ＋ V） type,two-phase,vapor-rich（L ＋ V） type,pure vapor（V） type,pure liquid（L） type and halite-bearing（L ＋ V ＋ S） type,which homogenized at 130 - 322 ℃（peak value： 160 - 220 ℃）,with corresponding salinities of 0. 18% - 17. 08%NaCl（average： 6. 12% NaCl）. The tectonic ore fluids predominantly consist of H2O,CH4 and minor N2 and CO2. In conclusion,the tectonic ore fluids are characterized by medium to low temperatures,medium to low salinities,which are distinctly different from the skarn stage ore fluids.

关 键 词：流体包裹体 构造热液成矿作用 羊拉铜矿床 滇西北 

分 类 号：P595[天文地球—地球化学]