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五台山—恒山绿岩带Au、Ag、Cu矿床可分为二大类型:(1)再生型金银铜矿,产在包括岩浆岩在内的各类岩石断裂构造中,与岩浆期后热液有关;(2)变生型金银铜矿,产于各类变质岩中,具有层控特征(即绿岩型金矿)。在地球化学特征上,再生型矿床与变生型矿床相比,矿体及围岩中Mo、Ag、Pb、Zn、Cd等成矿及伴生元素明显富集;K2O、Rb、Sr、Ba、Th、U也明显富集,是后期岩浆热液作用的结果;Hg、F的明显富集则与后期构造活动有关;Zn/Cd比值较低,说明受到后期岩浆侵入影响;Th/U比值低,可能指示富钙的酸性岩环境。再生型Au矿化的元素组合为Cd、As、Ni、Ag、Sb、Au、Hg(Bi),再生型Ag矿化的元素组合为As、Sb、Ag、Cd、Cu、Ni(Mo、Pb、Zn、Bi),变生型Au矿化的元素组合较简单,只为Au、Hg、As或Au、Cu。上述地球化学特征不仅可以有效地区分矿化类型,而且可以作为地球化学找矿和评价的指标
The Au, Ag and Cu deposits in the Wutaishan-Hengshan greenstone belt can be divided into two major types: (1) Regenerative Au-Ag-Cu deposits are produced in various types of rock faults including magmatic rocks, (2) Variation of gold, silver and copper ore, produced in all types of metamorphic rocks, with stratigraphic features (ie, greenstone type gold deposit). In terms of geochemical characteristics, the ore-forming elements and associated elements such as Mo, Ag, Pb, Zn and Cd in ore bodies and surrounding rocks are obviously enriched in reclaimed ore deposits compared with the metamorphic ones. K2O, Rb, Sr, Ba, Th and U are also obviously enriched, which is the result of late magmatic hydrothermal process. The obvious enrichment of Hg and F is related to the tectonic activity in the later stage. The lower Zn / Cd ratio indicates that it is affected by late magmatic intrusion. The Th / U ratio is low , May indicate an acid rock environment rich in calcium. The elemental composition of regenerated Au mineralization is Cd, As, Ni, Ag, Sb, Au and Hg (Bi) , Zn, Bi). The combination of alloying Au mineralization is relatively simple, only Au, Hg, As or Au, Cu. The above geochemical characteristics not only can effectively distinguish between mineralization types, but also can be used as an indicator of geochemical prospecting and evaluation