【作者】 胡芳芳； 范宏瑞； 于虎； 刘振豪； 宋林夫； 金成伟；

【Author】 HU FangFang,FAN HongRui,YU Hu,LIU ZhengHao,SONG LinFu and JIN ChengWei 1.Key Laboratory of Mineral Resources,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China 2.Shandong Jinzhou Mining Industry Group,Rushan 264501,China

【机构】 中国科学院地质与地球物理研究所矿产资源研究重点实验室； 山东金洲矿业集团有限公司；

【摘要】 三甲金矿是胶东牟平乳山金成矿带内重要的石英脉型金矿,金主要产于黄铁矿和多金属硫化物石英脉中。流体包裹体研究表明,三甲金矿蚀变岩石和各成矿阶段金矿石中的流体包裹体主要有三种类型:H₂O-CO₂包裹体、富CO₂包裹体和H₂O溶液包裹体。早期乳白色石英中主要赋存原生的H₂O-CO₂包裹体;成矿期黄铁矿石英脉和多金属硫化物石英脉中的富CO₂包裹体主要为原生,随机分布,气液比变化较大,常与早期H₂O溶液包裹体共生且均一温度接近,显示不混溶流体包裹体组合特征;在成矿晚期的石英和方解石中主要发育原生H₂O溶液包裹体。显微测温结果显示,成矿前（第Ⅰ阶段）H₂O-CO₂包裹体的完全均一温度(T_h,TOT,至液相)为280℃至416℃,成矿期（第Ⅱ和Ⅲ阶段）富CO₂包裹体的完全均一温度为210～330℃,同期的H₂O溶液包裹体均一温度为253～377℃,成矿后（第Ⅳ阶段）H₂O溶液包裹体的均一温度为176～207℃。成矿流体为低盐度的CO₂-H₂O-NaCl型热液,成矿应力场转变导致的流体减压沸腾作用可能是三甲金矿金沉淀成矿的主要原因。更多还原

【Abstract】 Sanjia gold deposit is a typical lode gold deposit in the Muping-Rushan gold belt of Jiaodong Peninsula,eastern China. Gold occurs mainly in pyrite- and polymetallic sulfide-quartz vein/veinlet stockworks.Fluid inclusions in the altered wallrocks and gold ores show CO₂-H₂O-NaCl fluids of three main types,namely H₂O-CO₂,CO₂-rich and aqueous inclusion.Early milk white quartz contains original H₂O-CO₂ inclusions.In the pyrite quartz vein and polymetallic-sulphide quartz vein,CO₂-rich inclusions occur in isolation or cluster with large range of H₂O/CO₂,whereas the aqueous inclusions occur as secondary trails in microfractures cutting earlier quartz grains.On occasion CO₂ -rich inclusions with variable aqueous phase were co-occurrence within the same clusters,and mostly homogenize to liquid or vapor at the same temperatures,indicating immiscibility did occur at the deposit.Quartz and calcite in the late ore-forming stage developed original aqueous inclusion.Microthermometric data show the homogenization temperatures of the CO₂-H₂O inclusions in the early ore-stage fall in the range between 280 and 416℃.Homogenization temperatures,obtained mainly from CO₂-rich inclusions with relatively small CO₂ bubbles in the main ore-stages,range from 210 to 330℃.Homogenization temperatures of H₂O aqueous inclusions at same stage with CO₂-rich inclusions are between 253 and 377℃,Homogenization temperatures（to liquid） of the aqueous inclusions in the late stage range from 176 to 207℃.Fluid immiscibility caused by change of mineralizing stress possibly led to the gold precipitation at Sanjia.更多还原