东疆卡拉塔格梅岭铜(金)矿床地质和流体包裹体特征及其与紫金山式铜金矿床的对比  

Geological and fluid inclusion characteristics of Meiling Cu-Au deposit in Kalatage ore belt,eastern Xinjiang,in comparison with typical Zijinshan-style HS-epithermal deposit

作　　者：缪宇[1] 秦克章[1] 许英霞[1] 方同辉[2] 丁奎首[1] 徐兴旺[1] 

机构地区：[1]中国科学院矿产资源重点实验室中国科学院地质与地球物理研究所 [2]北京矿产地质研究院,北京100012

出　　处：《矿床地质》2007年第1期79-88,共10页Mineral Deposits

基　　金：国家自然科学基金项目(40672069);中国科学院知识创新工程重要方向项目(KZCX3-SW-137);国家"十五"科技攻关新疆305项目东天山东段铜矿专题(2003BA612A-06-07)的联合资助

摘　　要：卡拉塔格成矿带梅岭铜（金）矿床位于新疆吐哈盆地南缘的古生代隆起带中，在大地构造位置上处于大南湖-突苏泉晚古生代岛弧带北段的上叠火山盆地中。其成矿阶段形成的石英中的流体包裹体类型较为单一，多为气液两相包裹体，数量少，个体较小（3～10μm），气相百分数小（4％～10％），零星随机分布。均一温度变于化106．6～259．8℃，成矿流体盐度w（NaCleq）为0．18％～8．41％，成矿压力为3～16MPa，估算的成矿深度为0．4～0．8km。结合野外观察以及火山-次火山岩石组合、热液蚀变组合及矿石结构构造与矿化特点，提出梅岭铜（金矿区为高硫化物浅成低温热液型与斑岩型铜金矿之间的过渡类型，相当于福建紫金山式或台湾金瓜石式。Located in the Paleozoic uplift along the southern margin of Tu-Ha basin in eastern Xinjiang, the newly discovered Meiling Cu-Au deposit occurs in the superimposed Mesozoic volcanic basin upon the northern part of Late Paleozoic Dananhu-Tousuquan accretionary arc. The Meiling Cu-Au deposit is controlled by NWW-SN- and EW- trending faults and can be divided into three Cu-Au sub-zones. Host rocks are mainly rhyolitic-dacitic ignimbrite, whereas Cu-Au mineralization is closely related to quartz porphyry, rhyolitic porphyry and granitic porphyry. Ore-forming styles are dominantly veinlet-disseminations and veinlets, and occasionally stockworks. The mineral association consists of chalcopyrite, pyrite, bornite, chalcocite and sphalerite. Typical minerals are alunite and pyrophyllite. Hydrothermal alterations are mainly silicfication, sericitization, alunitization, pyrophylitization, illitization, hydromuscovitization and chloritization. Fluid inclusions are very small （3-10 μm）and sparse, and gas to liquid ratios are 4 %- 10 %. The homogenization temperatures fall in the range of 107 260℃ ,with the salinities from 0.2% to 8.4% （w（NaCleq） 1, and the estimated pressure mainly from 3 to 16 MPa. Fluid inclusions and geological data suggest that the ore-forming process occurred in depths of 0.4 - 0.8 km. Based on field observation, volcanic sub-volcanic rock composition, hydrothermal alteration, ore structure and ore-forming characteristics, this paper holds that the Meiling Cu-Au deposit belongs to the transitional type from high-sulfidation epithermal deposit to porphyry Cu-Au deposit, corresponding to typical HS-epithermal deposits such as the Zijinshan Au-Cu deposit in Fujian and the Chinkuashih Au-Cu deposit in Taiwan.

关 键 词：地球化学 流体包裹体 高硫型浅成低温热液矿床 梅岭Cu-Au矿床 卡拉塔格成矿带 东天山 

分 类 号：P618.41[天文地球—矿床学] P618.51[天文地球—地质学]