西藏铁格隆南铜(金银)矿床地质特征及勘查模型——西藏首例千万吨级斑岩-浅成低温热液型矿床  

Geological Characteristics and Exploration Model of the Tiegelongnan Cu(Au-Ag) Deposit: The First Ten Million Tons Metal Resources of a Porphyry-epithermal Deposit in Tibet

作　　者：唐菊兴[1] 宋扬[1] 王勤[2] 林彬[1] 杨超[3] 郭娜[2] 方向[1] 杨欢欢[1] 王艺云[2] 高轲[2] 丁帅[2] 张志[4] 段吉琳[7] 陈红旗 粟登逵 冯军 刘治博[1] 韦少港[7] 贺文[7] 宋俊龙[2] 李彦波 卫鲁杰 

机构地区：[1]中国地质科学院矿产资源研究所,国土资源部成矿作用与资源评价重点实验室,北京100037 [2]成都理工大学,四川成都610059 [3]拉瓦尔大学地质学与地质工程学院,加拿大魁北克G1V0A6 [4]中国地质调查局成都地质调查中心,四川成都610081 [5]西藏地质矿产勘查开发局第五地质大队,青海格尔木816000 [6]西藏金龙矿业股份有限公司,西藏拉萨850000 [7]中国地质大学(北京),北京100083

出　　处：《地球学报》2016年第6期663-690,共28页Acta Geoscientica Sinica

基　　金：国土资源部公益性行业科研专项(编号:201511017);中国地质科学院院基本科研业务费(编号:YYWF201608);国家自然科学基金项目(编号:41172077;41402178);中国地质调查局青藏高原专项项目(编号:12120113037400);中铝资源西藏金龙矿业股份有限公司项目(编号:XZJL-2013-JS03)联合资助~~

摘　　要：铁格隆南矿床（荣那矿段）位于多龙矿集区多不杂斑岩型铜（金）矿的北东中部,铜（金）矿体的主要赋矿围岩为早白垩世中酸性斑岩及早中侏罗统色哇组（J1-2^s）复理石或类复理石建造;下白垩统美日切错组（K1m）陆相中基性火山岩建造（110Ma）覆盖在斑岩-浅成低温热液成矿系统之上,是该矿床得以良好保存的重要原因.通过详细的地质填图、地质编录、岩石地球化学、镜下鉴定、电子探针分析、流体包裹体分析、同位素年代学、岩石地球化学测量、音频大地电磁测深和综合研究,确定了矿体形态整体上为一个似筒状体,铜（金、银）矿体总体呈北东向,控制矿体北东延长约2000m,南东-北西向约1200m,Cu平均品位大于0.5%,伴生Au品位0.08g/t,伴生银品位2g/t左右,单个矿床铜资源量约1100万吨,远景资源量超过1500万吨.矿石以典型的细脉浸染状为主,从浅部至深部,金属矿物由铜蓝、蓝辉铜矿、斯硫铜矿、雅硫铜矿、久辉铜矿、斜方蓝辉铜矿及黄铜矿、斑铜矿（微量辉钼矿）,主要非金属矿物有明矾石、地开石、高岭石、水铝石、绢云母、石英、硬石膏等组成（图2-17）,矿物和蚀变组合显示高硫型浅成低温热液矿体叠加于斑岩型矿体.成矿岩体为120Ma侵位的花岗闪长斑岩,辉钼矿Re-Os同位素年龄显示斑岩成矿形成于119Ma左右,明矾石Ar-Ar同位素测年结果为116Ma左右,表明浅成低温热液型矿化略晚于斑岩型矿化.由于羌塘地体南缘的不断隆升,导致浅成低温热液矿化持续向深部迁移,形成巨厚典型的浅成低温热液矿物组合.流体包裹体研究表明,流体包裹体均一温度显示存在2套明显不同温度的流体,即形成斑岩及其围岩钾硅化与绢英岩化带矿化的中高温流体以及高级泥化带中的中低温流体,高温、高盐度的流体代表了斑岩系统的流体特征,而中低温、低盐度的流体代表了高硫The Tiegelongnan deposit is located in the middle of the northwest Duobuza porphyry Cu-Au deposit, and its primary ore host rock are Early Cretaceous porphyries and a suite of flysch formation or fly-schoid formation of Middle-Lower Jurassic strata, named Sewa Formation （J1-2s）. A suite of Meiriqiecuo intermediate-basic volcanic formation （K1m）, which was formed at 110 Ma in the post metallogenic period, lies upon the porphyry metallogenic system and is proved to be an essential element of ore preservation. With such means as detailed geological mapping, geological logging, lithogeochemical measurements, microscope observation, electron microprobe analysis, fluid-inclusion analysis, isotopic geochronology, audio magnetotelluric sounding and comprehensive research, the authors detected that the Cu-Au-Ag deposit is generally like a cylinder, trending northeast and stretching for about 2 000 meters in the northeast-southwest direction and 1 200 meters in the northwest-southeast direction. The average grade of Cu is greater than 0.5 percent and the average grade of associated Au and Ag is about 0.08 g/t and 2 g/t, separately. The resource of Cu is estimated to be about 11 megatons, and the prospective resources could be more than 15 megatons. Ores are mainly of typical veinlet disseminated structures. From top to bottom, the metallic minerals vary in a certain sequence, i.e., covellite, digenite, spionkopite, yarrowit, djurleite, anilite, chalcopyrite, bornite and a small amount of molybdenite, and the nonmetallic minerals vary in the same way, i.e., from top to bottom there are alunite, dickite, kaolinite, diaspore, sericite, quartz, anhedritite and so on. The typical minerals and the alteration mineral assemblage indicate that the deposit belongs to a porphyry-epithermal metallogenic system. The isotopic dating of different minerals gives us a clear mineralization sequence that the mineralization of epithermal system is later than porphyry’s. To be specifically, the data of granodio

关 键 词：矿床地质特征 勘查模型 斑岩-浅成低温铜(金 银) 铁格隆南 多龙 西藏 

分 类 号：P618.41[天文地球—矿床学] P611[天文地球—地质学]