投稿时间:2016-01-11
修订日期:2016-11-30
网络发布日期:2017-03-11
中文摘要: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δ34S值(0.3‰~1.2‰)非常接近深部地幔硫的值,其δ34S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。δ65Cu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(δ65Cu=-0.98‰~3.14‰)、矽卡岩型矿床(δ65Cu=-1.29‰~2.98‰)和热液脉型矿床中δ65Cu值(-3.70‰~0.44‰)的分布范围,其δ65Cu值变化范围大于岩浆矿床的δ65Cu值(-0.62‰~0.40‰),更接近于斑岩型矿床的δ65Cu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。
Abstract: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 δ34S(0.3‰~1.2‰) from massive ore and pyrite in granite porphyry in the Dongxiang mine are very close to the values of δ34S in deep mantle,whereas the δ34S values from sulfides exhibit tower distribution type and have a narrow distribution range, indicating that the δ34S was derived from deep source magma. The δ65Cu values of chalcopyrite have a narrow distribution range and are overall close to zero, which are distinctly different from the δ65Cu 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 δ65Cu values of chalcopyrite in magmatic deposits and porphyry deposits. The values of δ65Cu of the Dongxiang copper deposit(-2.10‰~0.17‰)are larger than the δ65Cu values of magma deposits(-0.62‰~0.40‰),but are close to the δ65Cu 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.
文章编号:
中图分类号:618.41
文献标志码:
基金项目:本文得到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
引用文本:
欧阳学财,狄永军,王长明,张达,杨秋,吴彬,王乔,罗政.2017.江西东乡铜矿床成因:铜和硫同位素联合约束[J].矿床地质,36(1):250~264OUYANG XueCai,DI YongJun,WANG ChangMing,ZHANG Da,YANG Qiu,WU Bin,WANG Qiao,LUO Zheng.2017.Genesis of Dongxiang copper deposit in Jiangxi Province: Constraints from copper and sulfur isotopes[J].Mineral Deposits36(1):250~264
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