黑色岩系中金属元素地球化学特征一直是矿床地质研究的重点.澳大利亚布朗斯Co-Cu-Ni多金属矿产于古元古代黑色岩系中,属典型的层控矿床;该矿床中主要成矿元素为Co、Cu、Ni和Pb,矿化分带不明显,蚀变微弱.δ34S均值范围为-5.21‰～14.78‰,估计生物成因的硫占一定比例,后期有细菌还原硫酸盐成因的高硫同位素组成硫的参与;铅同位素(206Pb/204Pb=16.20～16.22, 207Pb/206Pb=15.48～15.51, 208Pb/207Pb=35.86～35.92)表明矿床中铅的来源单一,均为壳源.矿床经历了沉积-成矿-后期热事件的微弱叠加改造.通过与中国南方黑色岩系对比,发现丰富的有机质在金属元素富集成矿过程中起重要作用.布朗斯多金属矿床属正常海水沉积成矿,与中国南方黑色岩系中多金属矿床有较显著区别.%The Browns Co-Cu-Ni deposit is hosted by the Whites Shale of Paleo-Preterozoic in Northern Territory of Australia, and it is a typical strata-hound deposit. Based on the analysis of the geological characters in detail, the major elements, trace elements, Pb and S isotope, and the organic matter, the enrichment mechanism of the ore metals is studied in this paper. The main Co-hosting mineral is siegenite, which is carried by pyrite. δ34S values of the sulfides range from -5.21％o to + 14.78％, indicating involvement of thermochemical reduction and bacterial activity. Homogeneous lead isotope features of galena ( 206 pb/204 Pb = 16. 20 ～ 16.22, 207 pb/206 Pb = 15.48 ～15.51, 208Pb/207pb =35.86 ～ 35.92) suggest that Pb was derived from the erust. Ore geochemical studies illustrate that the deposit is primarily of sedimentary origin and were somewhat reformed by later tectonic-thermal events. Compared with the deposits hosted in the South China black shales, it can be concluded that the Browns deposit is a normal sedimentation deposit, while the latter are Sedex-type deposits.
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