吉尔吉斯斯坦布丘克造山型金矿床:来自流体包裹体、H-O-S同位素证据  

The Buchuk orogenic gold deposit in Kyrgyzstan: Evidences fromfluid inclusions and H-O-S isotopes

作　　者：史鹏亮 屈海浪 鄂建新[1] 刘春发 缪广 马麒镒[1] 戴毅 SHI Pengliang;QU Hailang;E Jianxin;LIU Chunfa;MIAO Guang;MA Qiyi;DAI Yi(China Gold Group Geology Co.,Ltd.,Beijing 101300,China;School of Earth Sciences and Resources,China University of Geosciences,Beijing 100083,China)

机构地区：[1]中国黄金集团地质有限公司,北京101300 [2]中国地质大学(北京)地球科学与资源学院,北京100083

出　　处：《地质学报》2023年第3期738-752,共15页Acta Geologica Sinica

基　　金：中国黄金集团有限公司“一带一路”地质科研项目(编号WKY201906)资助的成果。

摘　　要：吉尔吉斯斯坦北天山构造带的矿床学数据缺乏,制约了天山造山带境内外成矿对比。布丘克金矿床位于吉尔吉斯斯坦北天山构造带中部。金矿体为石英复脉,呈带状发育于NWW向韧性剪切带中。矿体倾向SSW,倾角60°~70°,赋矿围岩主要为侵入于早古生代变质碎屑杂岩中的正长斑岩。布丘克金矿床成矿期石英流体包裹体观察、石英H-O同位素、硫化物S同位素测试结果显示,布丘克金矿床石英脉中包裹体大小集中在2~10μm之间,类型以H2O-CO_(2)型、富CO_(2)型、水溶液型包裹体为主,成分以富CO_(2)、含CH4为特征。成矿流体具有中温(200~320℃)、低盐度(3%~7%NaCleqv)特征;石英δDV-SMOW值介于108.1‰~90.2‰之间,δ18O流体值介于4.86‰~9.26‰之间;黄铁矿δ34S分布在0‰左右(0.9‰~1.6‰)。综合本文数据、矿床地质特征、区域地质资料,本文认为布丘克金矿床为发育于吉尔吉斯斯坦北天山构造带内的造山型金矿床,韧性剪切带控制了成矿作用过程;成矿热液来自含碳地层的变质脱水作用,成矿物质来自深部岩浆岩。The lack of data on mineral deposits in the North Tianshan tectonic belt of Kyrgyzstan restricts the comparison of mineralization in China and abroad in the Tianshan orogenic belt.The Buchuk gold deposit is located in the middle of the Kyrgyz North Tianshan tectonic belt.The gold ore bodies are developed in the NWW-trending ductile shear zone in the form of quartz complex veins.The ore body is inclined to SSW,with a dip angle of 60°~70°.The ore-hosting wall rock is mainly syenite porphyry intruded into the Early Paleozoic metamorphic clastic complex.The observation of quartz fluid inclusions,quartz H-O isotope,and sulfide S isotope test results show that the size of the inclusions in the quartz veins of the Buchuk gold deposit is concentrated between 2~10μm,and the types of inclusions are mainly H2O-CO_(2) type,CO_(2)-rich type,and aqueous solution type.The components of fluid inclusions are characterized by being rich in CO_(2) and containing CH4.The ore-forming fluid has the characteristics of mesothermal(200~320℃)and low salinity(3%~7%NaCleqv).The quartzδDV-SMOW values range from 108.1‰to 90.2‰,andδ18Ofluid fluid values range from 4.86‰to 9.26‰;the pyritesδ34S are distributed around 0‰(0.9‰to 1.6‰).Based on the data in this paper,the geological characteristics of the deposit,and the regional geological data,this paper proposes that the Buchuk gold deposit is an orogenic gold deposit developed in the North Tianshan tectonic belt in Kyrgyzstan,and ductile shear zone controls the mineralization process.The ore-forming hydrothermal fluids come from the metamorphic dehydration of carbon-bearing strata,and the ore-forming materials come from deep magmatic rocks.

关 键 词：吉尔吉斯斯坦 北天山构造带 布丘克金矿床 流体包裹体 稳定同位素 造山型金矿 

分 类 号：P618.51[天文地球—矿床学]