【作者】 杨爽；

【导师】 杜杨松；

【作者基本信息】 中国地质大学(北京) ， 矿物学、岩石学、矿床学， 2012， 硕士

【摘要】 安徽铜陵地区是长江中下游多金属成矿带的一个重要组成部分。冬瓜山铜矿床是安徽铜陵地区一个有代表性的层控矽卡岩型铜矿床，其矿床规模较大，地质特征独特，具有典型意义。本文对冬瓜山铜矿床进行了岩相学、矿物学和地球化学研究，取得了以下主要成果。1、野外及显微观察发现，安徽铜陵冬瓜山铜矿矿石兼具沉积、热变质、热液交代三种不同的结构构造。2、矿物学研究表明，冬瓜山铜矿床主矿体中的磁黄铁矿是早期纹层状矿体中的黄铁矿在燕山期强烈变质作用下发生脱硫作用形成的，其形成过程中经历了缓慢的降温过程，局部也存在一个快速降温过程。3、矿相学和同位素研究表明，冬瓜山铜矿床中的铜可能来源于岩浆热液。4、综合研究显示，冬瓜山层控矽卡岩铜矿经历了两期成矿作用。早期晚石炭世海底喷流和热水沉积在矿床底部形成了大量以硫铁为主的含铜矿胚层；晚期燕山期岩浆活动，致使成矿系统内的物理化学条件发生变化，岩浆热液对早期形成的矿胚层进行叠加改造，并使铜加厚变富后沉淀，最终形成了层控矽卡岩型铜矿床。更多还原

【Abstract】 Tongling area in Anhui Province is an important part of the Middle-lowerYangtze River polymetallic metallogenic belt. Dongguashan copper deposit is one ofrepresentative stratabound skarn Cu deposits in Tongling, Anhui Province. It is typicaldue to its large scale, high grade and remarkable geologic feature. A comprehensivepetrographical, mineralogical and geochemistry study has been carried out on theDongguashan copper deposit, with a focus on analyses of ore texture and structureand mineral composition.The following are major achievement obtained in this thesis.1. Field investigation and microscopic observation indicate occurrence ofsedimentary, thermally metamorphic, and hydrothermal metasomatic textures andstructures in ores from the deposit.2. Compositional analyses of minerals support formation of pyrrhotite in themain ore body of the Dongguashan copper deposit by desulfurization of pyrite in theearly laminated ore body during the Yanshanian intense metamorphism. A slowcooling process occurred during its formation, locally with a rapid cooling process.3. A mineralographical and isotopic research shows derivation of Cu in theDongguashan copper deposit possibly from the Yanshanian magmatic fluid.4. Two periods of mineralization are responsible for the formation of theDongguashan Cu deposit. The early mineralization of the late Carboniferoussubmarine exhalative and sedimentation led to formation of many copper sources bedswith S and Fe in the basement of the deposit. In contrast, the late mineral of theYanshanian magmatic activity resulted in formation of stratabound skarn Cu depositthrough variation of physicochemical conditions in the metallogenic system andsuperimposed reformation of early sources beds by the magmatic fluid.更多还原