Abstract:Lying in Upper Proterozoic metamorphic volcanic-sedimentary sequence, the Weishancheng gold-silver deposit is both controlled by lithological characters or the strata and characterized by evident hydretnermal mineralization. Considerable geochemical and stable isotopic data reveal that this area has concentrated ore-forming elements, predominantly silver. Waitoushan zu (Pt3w) secnis to be an ore-bearing stratum and Pt3w2 and Pt3w3 are likely the source bed of gold and silver,. Gold, silver and their associated sulfur and lead all came from the same source, i.e., from the mantle or the depth of the crust. No obvious connection has been observed between geochemical netting of Hercyniau and Yenshanian granitoids surrounding the deposit and amounts of metallogenic elements such as gold and silver in the source bed, suggesting that; granitoids were not the source of ore materials. The model ages of lead from the ore are 810-970 m. y., quite in agreement with the age of the surrounding strata. Four phases of mineralization could be recognized: 1) Volcanic-sedimentation phase: ore materials were derived from volcanic debris and ore source bed was formed through the adsorption of gold and silver by carbonaceous materials; 2) Regional metamorphism phase: tne ore-bearing materials carried by metamorphic fluids precipitated at low-pressure zone, forming ore at middle and low temperatures; 3) Thermometamorpnism phase: the temperature-pressure conuions caused by activiey of late acid magma further concentrated ore-forming materials in part of ore source bed; 4) Leaching, phase: the secondary enrichment after the formation of ore deposit has augmented the ore grade at shallower depths. In short, the author holds the opinion that the commercial accumulation of the Weishancheng gold-silver deposit has been reached through repeated concentration of such metallogenic elements as gold and silver in certain areas under the action of multiple geologic processes. This deposit, therefore, is of polyphase and polygenetic type.
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陈殿凯,周旦生.1984.围山城层控金银矿特征和成矿作用[J].矿床地质,3(1):37~46.1984.Stratabound features and mineralization process of the Weishancheng gold-silver deposit[J].Mineral Deposits3(1):37~46
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