沉积岩容矿的层状铜矿床成因——以澳大利亚布朗斯(Browns)铜多金属矿床为例  

Genesis of sedimentary rock-hosted stratiform copper deposit——a case study on Browns Cu-polymetallic deposit,Australia

作　　者：夏浩东[1] 王明艳 邓会娟[1] 

机构地区：[1]国土资源实物地质资料中心,河北三河065201 [2]湖南有色金属控股集团矿产资源部,长沙410015

出　　处：《世界地质》2011年第3期323-334,共12页World Geology

基　　金：国土资源部"2008年度境外矿产资源风险勘探财政补贴"项目;国家科技攻关计划课题(2003BA612A-05);国家自然科学基金资助项目(41002027)联合资助

摘　　要：以澳大利亚布朗斯Cu多金属矿床为例,研究了该矿床的地质与地球化学特征,认为该矿床是在"饥饿"沉积阶段富集了Cu、Pb、Zn等金属元素,在后期盆地卤水作用下形成矿化的一个"沉积-改造"矿床。在此基础上,对比分析了赞比亚铜矿带、波兰Kupfershierfer铜矿带和中国云南东川铜矿床,总结了该类铜矿床成矿的一般规律,认为该类矿床的金属物质一般来源于下伏红层/风化基底;S一般来自于蒸发岩和黑色页岩,个别矿床古油气藏也提供了S源;成矿流体为中-高盐度、中温的氧化性盆地卤水,成矿物质主要以络合物(CuCl_3^-)的方式运移,流体驱动动力一般是区域性构造运动,放射性衰变生热和盐丘底劈也能够导致流体运移;金属矿物沉淀的主要机理是还原反应,主要还原剂是原地有机质;在盆地演化过程中,成矿金属元素在氧化还原界面上与S结合沉淀析出,形成矿化。Taking the Browns Cu-polymetallic deposit as an example, the authors study its geological and geochemical characteristics. It is believed that the Cu, Pb and Zn were enriched during ＂hungery＂ deposition stage, and formed a sedimentary-reformed deposit mineralized by brine effect of later basins. On the basis, the authors conclude the metallogenie regularity of this kind of Cu deposit by constrasting with the Zanbian copper belt （ ZCB ）, Kupferschiefer copper belt in Poland, and Dongehuan copper belt in Yunnan of China. It is considered that the metallic minerals are commonly sourced from the underlying red-bed and weathered basement; the sulfur is from the evaporite and black shale/mudstone, and rarely from the ancient hydrocarbon reservoirs. The metallogenic fluid are mid-high salinity and intermediate temperate oxidized basin brine. The metallogenic minerals transport mainly as Cl-eomplex （ CuCl3- ）, and the driver force of fluid flow are tectonic activity, radiation heat and salt diapir can also lead to fluid transportation. Reduction is the main mechanism of metallic minerals precipitation, and in-situ organic matter is the main reducing agent. The metallic minerals combined with S and precipitated on oxidation-reduction interface, and mineralized during the basin evolution.

关 键 词：沉积岩容矿 铜矿床 矿床成因 布朗斯 澳大利亚 

分 类 号：P618.41[天文地球—矿床学]