| 新疆红十井金矿床特征及成因 |
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| 引用本文：.2003.Characteristics and Genesis of Hongshijing Gold Deposit, Xinjiang[J].Mineral Deposits,22(1):32~40 |
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| 基金项目:国家305项目（编号96-915-05-05），南京大学内生金属矿床成矿机制研究实验室基金和南京大学现代分析中心基金 |
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| 中文摘要:文章通过K-Ar同位素年龄，氢、氧、硫、铅等同位素测试和流体包裹研究，结合红十井金矿床的地质、矿区岩石化学、微量元素及稀土元素地球化学特征，探讨了红十井金矿床含金建造与金矿关系及矿床成因。研究表明红十井金矿床为晚古生代裂谷带火山岩区受韧性剪切带控制的中_低温热液矿床，矿体赋存于中石炭统玄武(玢)岩及凝灰质砂岩组成的含金建造内，成矿物质主要来源于含金建造，矿化以蚀变岩型和石英脉型为主。成矿年龄为209～267 Ma。成矿流体为岩浆水、玄武(玢)岩和凝灰质砂岩的变质水、建造水和大气降水的混合溶液，δD为-114.6‰～-68.8‰，δ18 O H2O变化为-2.47‰～5.91‰。成矿温度为115～381℃,成矿压力为471.8×105～675.9×105 Pa；流体盐度w(NaCleq)为2.18%～16.77%，平均7.79%，流体属中-低盐度、H2O-CO2体系。 |
| 中文关键词:地球化学 金矿床 成因 红十井 新疆 |
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| Characteristics and Genesis of Hongshijing Gold Deposit, Xinjiang |
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| Abstract:The Hongshijing gold ore deposit, which occurs in the volcanic rock and pyroclastic rock of the middle and late Carboniferous Period, is of brittle-ductile shear zone type controlled by the rift belt. There are altered_rock type and quartz type orebodies, which are contained in gold-bearing formation consisting of basalt and tuffaceous-sandstone. The gold content of the gold-bearing formation is 2.4×10-9. The major ore-forming stage is 267～261 Ma and the superimposition ore-forming stage is 220～209 Ma.The ore minerals include pyrite, magnetite, copper, bornite, ferrohydrite and native gold, whereas the gangue minerals include quartz, sercite, calcite, Fe-dolomite, leucoxene, anorthose, biotite, cajuelite, agustite etc. The wall rock alteration associated with gold mineralization comprises silicification, carbonization, pyritization, sericitization and chloritization. Geochemical investigation reveals that the mineralizing material came from the basalt and tuffaceous-sandstone in the gold-bearing formation. Under the action of ductile brittle shear structure, the gold_bearing formation was metamorphosed and altered, and the ore-forming material underwent activation, migration and mineralization. The ore-forming fluid shows characteristics of mantle fluid and has middle to low temperature (381～115℃) and middle to low mass fraction of NaCl (2.18%～16.77%) and H2O-CO2 system. According to the data of hydrogen and oxygen isotopic compositions (δD=-114.6‰～-68.8‰，δ18OH2O=-2.47‰～5.91‰), the conclusion can be reached that the ore-forming fluid of the Hongshijing gold deposit was a kind of mixed hydrothermal solution mainly composed of meteroric water, magmatic water and formation water in basalt and tuffaceous-sandstone or metamorphic water. Under the action of brittle shear, the gold-bearing formation was metamorphosed and altered, and the ore_forming material activated, migrated and mineralized with the change of the physical and chemical conditions at the depth of 1.57～2.25 km below the earth's surface. |
| keywords:geochemisty, gold deposit, genesis, Hongshijing, Xinjiang |
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