赞比亚铜带省铜矿成因分析

中非(赞比亚―刚果(金))沉积型铜矿以其拥有高品位的大型超大型铜、钴矿床和众多的世界级铜矿山而闻名于世。铜矿类型可分为沉积型铜矿、热液脉型铜矿、变质热液型铜矿三类。沉积型铜矿床形成后,受到深部含矿岩浆热液的侵入形成脉状铜矿,可能还有斑岩型铜钼矿的成矿作用,叠加富集原有的沉积型铜矿床。硫同位素结果显示,硫源主要为成岩硫化物和海水硫酸盐的混合硫,受到深源岩浆或岩浆热液叠加改造。沉积型铜矿成矿年龄880~735Ma,后期岩浆热液型铜钼矿成矿年龄为514~502Ma。这些发现对进一步认识总结中非铜矿带上的矿床成因及成矿规律具有重要意义。

Genesis of copper deposits in Copperbelt of Zambia

The sedimentary copper deposits in Central Africa (Zambia-D.R.Congo)are renowned for the high-grade super-large copper and cobalt deposits and numerous world-class copper mines.The types of copper deposits include sedimentary type,hydrothermal vein type and metamorphic hydrothermal type.After its formation,sedimentary copper deposit forms vein type copper deposit under the influence of intrusion of ore-bearing magmatic hydrothermal solution in deep part.The original sedimentary copper deposit is super-imposed and enriched through the possible ore-forming process of porphyry type copper-molybdenum deposit. The sulfur isotope indicates that the sulfur source,which is mainly mixed sulfur of diagenetic sulfide and seawater sulfate,is superimposed and transformed by deep-seated magma or magmatic hydrothermal solu-tion.The metallogenic age of sedimentary type copper deposits ranges from 880 to 735 Ma,and that of mag-matic hydrothermal-type copper cobalt deposits ranges from 5 14 to 502 Ma.The findings have important implications for further understanding of genesis and metallogenic regularity of deposits in Central Africa copper ore belt.