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安徽铜陵铜官山铜矿田是中国长江中、下游铁、铜、硫、金成矿带中著名的夕卡岩型矿床。小铜官山铜矿床位于安徽铜陵铜官山矿田,侵入岩体为铜官山石英二长闪长岩。成矿过程包括夕卡岩阶段、石英-硫化物阶段和石英-碳酸盐阶段3个主要成矿阶段。笔者通过对小铜官山铜矿床的氢、氧、碳、硫、硅同位素组成和稀土元素地球化学特征研究,探讨成矿溶液中水、硅和硫的来源以及成矿溶液的演化问题。研究表明,成矿热液早期以岩浆热液为主,随着成矿过程的进行,加入的大气降水比重越来越大,到晚期可能主要以大气降水为主。硫的来源主要有两个方面,即地层和岩浆热液,但以后者为主。硅具深部岩浆或岩浆热液水来源的特点。稀土元素球粒陨石标准化组成模式为右倾型,夕卡岩、矿石的稀土配分曲线类似于铜官山岩体石英二长闪长岩,故认为形成本区的夕卡岩型矿床的热液流体主要来源于闪长质熔体。
Tonglingshan Copper Mine, Tongling Mountain, Anhui Province, is a well-known skarn deposit in the iron, copper, sulfur and gold metallogenic belt in the middle and lower reaches of the Yangtze River in China. The small Tongguanshan copper deposit is located in the Tonggoushan orefield in Tongling, Anhui Province, and intrusive rocks are the Tonggoushan quartz diorite. The metallogenetic processes include three major metallogenic stages of the skarn stage, the quartz-sulphide stage and the quartz-carbonate stage. Based on the study on the isotopic compositions of hydrogen, oxygen, carbon, sulfur and silicon and the geochemical characteristics of rare earth elements in the Xiaogunshan copper deposit, the author explores the sources of water, silicon and sulfur and the evolution of ore-forming solutions in ore-forming solutions. The results show that the hydrothermal fluid is dominated by magmatic hydrothermal fluid in the early stage, and the proportion of atmospheric precipitation added to it increases with the progress of mineralization, which may be dominated by atmospheric precipitation in the late stage. There are two main sources of sulfur, namely, strata and magmatic hydrothermal fluids, but the latter are predominant. Silicon with deep magmatic or magmatic hydrothermal water source characteristics. The normalized compositional pattern of REE chondrites is right-inclined, and the REE distribution curves of skarn and ore are similar to that of Tonggoushan intrusive quartz diorite. Therefore, it is considered that the hydrothermal fluid that forms the skarn-type deposits in this area Mainly from the diorpha long melt.