江西东乡铜矿床成因：铜和硫同位素联合约束  

Genesis of Dongxiang copper deposit in Jiangxi Province:Constraints from copper and sulfur isotopes

作　　者：欧阳学财 狄永军[1] 王长明[1,3] 张达[1] 杨秋[1] 吴彬 王乔[1] 罗政[1] OUYANG XueCai DI YongJun WANG ChangMing ZHANG Da YANG Qiu WU Binl WANG Qiao(China University of Geoseienees, Beijing 100083, China No. 266 Geological Party, Jiangxi Bureau of Nuclear Industry Geology, Nanchang 330038, Jiangxi, China CET at the University of Western Australia, Perth 6009, Australia)

机构地区：[1]中国地质大学地球科学与资源学院,北京100083 [2]江西省核工业地质局266大队,江西南昌330038 [3]西澳大利亚大学CET研究中心,澳大利亚珀斯6009

出　　处：《矿床地质》2017年第1期250-264,共15页Mineral Deposits

基　　金：中国地质调查局南京地质调查中心项目“北武夷成矿带东乡浩家岭-上饶梨子坑铜多金属成矿规律及找矿方向研究(编号:1212011220557)"资助

摘　　要：东乡铜矿床的赋矿岩石以石炭系砂岩和燕山期花岗斑岩为主。文章对东乡铜矿床同位素地球化学进行了研究,探讨了成矿物质来源及矿床成因。东乡矿区块状矿石和花岗斑岩的黄铁矿δ^(34)S值(0.3‰~1.2‰)非常接近深部地幔硫的值,其δ^(34)S值呈现明显的塔式分布,分布范围较窄,表明矿石中的硫主要来自深源岩浆。δ^(65)Cu值分布范围较窄(-2.10‰~0.17‰),整体接近于零附近,明显不同于块状硫化物矿床(δ^(65)Cu=-0.98‰~3.14‰)、矽卡岩型矿床(δ^(65)Cu=-1.29‰~2.98‰)和热液脉型矿床中δ^(65)Cu值(-3.70‰~0.44‰)的分布范围,其δ^(65)Cu值变化范围大于岩浆矿床的δ^(65)Cu值(-0.62‰~0.40‰),更接近于斑岩型矿床的δ^(65)Cu值(-1.16‰~0.81‰),表明东乡铜矿与岩浆热液作用具有密切的成因联系。因此,推断东乡铜矿为岩浆热液型矿床。The Dongxiang copper deposit is mainly hosted in the Carboniferous sandstone and Yanshanian granite porphyry.In this paper,the authors investigated the ore-forming materials sources and deposit genesis based on its isotope geochemistry.The values of δ-（34）S（ 0.3‰ - 1.2‰） from massive ore and pyrite in granite porphyry in the Dongxiang mine are very close to the values of δ-（34）S in deep mantle,whereas the δ-（34）S values from sulfides exhibit tower distribution type and have a narrow distribution range,indicating that the δ-（34）S was derived from deep source magma.The δ-（65）Cu values of chalcopyrite have a narrow distribution range and are overall close to zero,which are distinctly different from the δ-（65）Cu values of chalcopyrite in massive sulfide deposits（- 0.98‰ - 3.14‰）,skarn type deposits（- 1.29‰ - 2.98‰） and hydrothermal vein type deposits（- 3.70‰ - 0.44‰）,but are similar to the δ-（65）Cu values of chalcopyrite in magmatic deposits and porphyry deposits.The values of δ-（65）Cu of the Dongxiang copper deposit（- 2.10‰ - 0.17‰） are larger than the δ-（65）Cu values of magma deposits（- 0.62‰ - 0.40‰）,but are close to the δ-（65）Cu values of porphyry deposits（- 1.16‰ - 0.81‰）,suggesting that the Dongxiang copper deposit had close genetic relationship with magmatism.Therefore,according to the isotope analytical results of the Dongxiang copper deposit,it can be concluded that the Dongxiang copper deposit is a magmatic hydrothermal type deposit.

关 键 词：地球化学 成因 铜-硫同位素 物质来源 东乡铜矿 

分 类 号：R618.41[医药卫生—外科学]