山东玲珑九曲金矿床地质特征及流体包裹体研究

Geological characteristics and fluid inclusions of Jiuqu gold deposit in Linglong,Shandong

山东玲珑九曲金矿床位于金矿田的东部,属石英脉-蚀变岩型金矿床,矿化分为4个阶段,黄铁矿-石英脉阶段,石英-黄铁矿阶段,多金属硫化物阶段和石英-碳酸盐阶段。流体包裹体研究表明,九曲金矿床主成矿阶段石英中发育气液两相和含CO2三相包裹体,也可见少量的富气相包裹体。气液两相包裹体均一温度范围为133.5℃～325.7℃,峰值为290℃～310℃,盐度为2.80%～17.82%NaCl;含CO2三相包裹体均一温度范围为236.5℃～315℃,出现两个峰值,为230℃～240℃和310℃～320℃,盐度为0.41%～8.92%NaCl;富气相包裹体均一温度范围为222.1℃～236.4℃,峰值为230℃～240℃,盐度为7.71%～9.98%NaCl。综合地质条件、矿床特征和包裹体显微测温结果认为:九曲金矿床成矿流体为中温、中低盐度的NaCl-H2O-CO2型体系,矿床属中温岩浆热液成因类型。

The Jiuqu gold deposit of Linglong is a quartz vein-altered type gold deposit. The mineralization process can be classified into four stages： pyrite-quartz phase, quartz-pyrite phase, polymetallie sulfides and quartz-carbonate phases. The study of fluid inclusion shows that aqueous two-phase, CO2-bearing three-phase and minor gas-rich fluid inclusions developed in quartz of the main mineralization in Jiuqu gold deposit. Fluid inclusion indicates that the aqueous two-phase homogenization temperature ranges from 133.5 ℃ to 325.7 ℃ with the peak value between 290 ℃ and 310 ℃, salinity varies from 2. 80% to 17.82 % NaC1. The CO2-bearing three-phase homogenization temperature ranges from 236.5 ℃ to 315 ℃ with two peak values as 230 ℃ N240 ℃ and 310 ℃ 320 ℃ , salinity varies from 0.41% to 8.92% NaC1. The gas-rich fluid inclusion homogenization temperature ran- ges from 222. 1 ℃ to 236.4 ℃ with the peak value between 230 ℃ and 240 ℃, salinity varies from 7.71% to 9.98% NaC1. Comprehensive study of ore-forming condition, geological features and microthermometic analysis of fluid inclusions leads to the conclusion that the ore-forming fluid of the Jiuqu gold deposit belongs to the NaC1-H20 -CO2 hydrothermal system with medium temperature and medium-low salinity. The deposit is middle-temperaturemagmatic and hydrothermal in origin.