中文摘要:世界上的含金矽卡岩大多属钙矽卡岩型，镁矽卡岩金矿床十分稀少。本文介绍我国安徽北部三铺地区镁矽卡岩金（铜、铁）矿床的地质地球化学特征。该区含金（铜、铁）镁矽卡岩主要产于地台断拗区燕山期石英二长闪长玢岩与中上寒武统白云质大理岩外接触带。岩体内接触带发育钙矽卡岩和钾长石化，局部有辉钼矿话产出。金矿化与铜的硫化物密切共生，属于镁矽卡岩的退化热液交代作用产物。金属矿化分带序列自蚀变石英二长闪长玢岩到镁矽卡岩、蛇纹岩化白云质大理岩依次为：Mo→Fe→Cu（Au）。矿物共生组合和流体包裹体研究表明，交代成矿作用的演化可分为3个阶段：① 镁（钙）矽卡岩阶段；② 铁（镁）氧化物阶段；③ 碳酸盐（石英）-硫化物和金矿化阶段。
Abstract:Au skarns in the world arc mostly calcicones, and magnesian Au skarns are rarely seen. In this paper, the geological and geochemical characteristics of the Au (Cu, Fe) magnesian skarn deposits in Sanu area, Anhui Province, are described. The Au (Cu, Fe) magnesian skarn deposits of Sanpu arca occur in thc exocontact zones between Yanshanian quartz monzodiorite porphyry and Middle-Upper Cambrian dolomitic marble of the platformal fault depression zone and are located just in the upper mantle uprise. Magnesian skarns consist of diopside, forsterite, phlogopite, chondrodite, clinohumite, and have been subjected to strong serpentinization. clinochloritization and carbonitization associated with iron, gold and copper sulfide mineralization. In the endocontact zones, there are diopside-garnet-epidote calcic skarns associated with K-feldspathization of adjacent quartz monzodiroite porphyry. Locally, molybdenite mineraization occurs in the fractural zones of the K-feldspathized quartz monzodiorite porphyry. The mineralization zoning in some depsoits is very clear. The zonal sequence from altered quartz monzodiorite porphyry through magncsian skarn to serpentinizcd dolomitic marble is Mo→Fe→Cu (Au)→Au (Cu). Studies of the mineral paragenesis and fluid inclusions suggest that the metasomatic mineralization may be divided into three stages: ① magnesian (calcic) skarn stage; ② iron (magnesian) oxide stage forming magnetitie, magnesiomagnetite and magnesioferrrite; ③ carbonate (quartz) sulfide and gold mineralization stage. The formation temperature of magnesian skarn stage is 400～625℃ with salinites of 38. 4%～59.7% NaCl. The last two stages correspond to the retrograde hydrothermal metasomatic stage of the early magnesian skarns. The formation temperatures of these two stages are 180~450℃ with slainities of 17.8%～31% NaCl. The pressure of the petrogenesis and metallization is from 23.6 MPa to 612.9 MPa.
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基金项目:国家自然科学基金（49573184）
引用文本：
赵一鸣，张轶男，毕承思，唐开健，孙庆安.1999.安徽淮北三铺地区镁夕卡岩金（铜、铁）矿床生成地质环境、分带和流体演化[J].矿床地质,18(1):1~10，36.1999.The Metallogenic Geological Setting, Zonation and Fluid Evolution of the Au (Cu, Fe) Magnesian Skarn deposits in Sanpu[J].Mineral Deposits18(1):1~10，36
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