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为了了解抱伦金矿的成因条件,利用岩相学和拉曼光谱分析方法对不同期次含金石英脉中流体包裹体进行系统、深入的研究.结果表明,石英中流体包裹体可分为2种类型,即CO2-H2O包裹体和H2O溶液包裹体.CO2-H2O包裹体以CO2为主,含有CH4,主要存在于成矿期金-石英脉和金-多金属硫化物脉中,多为原生包裹体,孤立分布或成群分布,气液比变化大,显示不混溶流体包裹体组合特征.H2O溶液包裹体,主要存在于石英-碳酸盐脉中.显微测温结果显示,成矿期Ⅰ和成矿期Ⅱ包裹体的均一温度范围分别为248～376℃和213～320℃,成矿后流体包裹体的均一温度为140～244℃.成矿流体主要为CO2-H2O-NaCl热液体系,在成矿期Ⅰ和成矿期Ⅱ主要为中、低盐度(0.80%～16.05%NaCl equiv),并且富含挥发分(密度0.21～0.85g/cm3);在成矿期后,温度、盐度和CO2含量都相对降低;成矿晚期,方解石碳、氧同位素δ13 C(PBD,‰)和δ18 O(PBD,‰)分别在-6.86～-13.14和-10.64～-14.51之间,均指示流体主要以深源岩浆为特征,流体在运移过程中发生了水岩反应、蚀变,同时受到围岩有机质的混染.这种水岩反应以及由温度和压力降低所导致的不混溶作用可能是金矿金沉淀的主要因素.
In order to understand the genetic conditions of Baolun gold deposit, the fluid inclusions in different periods of goldiferous quartz veins were systematically and deeply studied by petrography and Raman spectroscopy.The results show that the fluid inclusions in quartz can be divided into There are two types of inclusions, CO2-H2O inclusions and H2O inclusions.The CO2-H2O inclusions are dominated by CO2 and contain CH4, mainly in the gold-quartz vein and gold-polymetallic sulfide veins in the ore-forming period For the primary inclusions, isolated or clustered distribution, the gas-liquid ratio changes greatly, showing the immiscible fluid inclusions .H2O solution inclusions mainly exist in the quartz-carbonate pulse.The results of the microscopic temperature measurement , The homogenization temperature range of mineral inclusions I and mineralization Ⅱ inclusions are 248 ~ 376 ℃ and 213 ~ 320 ℃, respectively, and the homogenization temperature of the fluid inclusions is 140 ~ 244 ℃ .The ore-forming fluid is mainly CO2- The H2O-NaCl hydrothermal system is characterized by medium and low salinity (0.80% ~ 16.05% NaCl equiv) and high volatility (density 0.21 ~ 0.85g / cm3) After the metallogenic stage, the temperature, salinity and CO2 content all decreased. In the late stage of metallogenesis, the δ13C (PBD, ‰) and δ18 O (PBD, ‰) are between -6.86 ~ -13.14 and -10.64 ~ -14.51, respectively, indicating that the fluids are mainly characterized by deep-source magmatic fluids. Water-rock reactions and alterations occur during fluid migration Surrounding rock organic matter contamination.This water-rock reaction and the immiscibility caused by the temperature and pressure reduction may be the main factors of gold deposit.