黝铜矿热力学计算热液矿床成矿温度——以山西义兴寨脉状金矿为例

Mineralization Temperature Calculated from Tetrahedrite Thermodynamic:Implication for Vein-type gold Mineralization in the Yixingzhai Gold Deposit,Shanxi

热液矿床成矿温度的准确限定是正确理解成矿作用过程和矿床成因的重要前提。为查明山西义兴寨金矿床的成矿温度,本文对不同期次脉状金矿中的黝铜矿和银金矿开展了电子探针元素分析和热力学计算。研究结果表明义兴寨矿床脉状金矿黄铁矿−石英阶段、黄铁矿−黄铜矿−石英阶段和石英−多金属硫化物阶段的成矿温度分别为290~300℃、(330±10)℃、(250±10)℃。该结果与此矿床不同阶段流体包裹体均一温度一致,且更为精确,表明黝铜矿热力学温度计能准确地限定热液矿床的成矿温度。

Accurate determination of the mineralization temperature of hydrothermal deposits is crucial to un-derstanding the processes and genesis of hydrothermal ore deposits.In order to find out the mineralization tem-perature of the Yixingzhai gold deposit in Shanxi Province,this paper carried out electron microprobe elemental analyses and thermodynamic calculations on the tetrahedrite and electrum from the different stages of vein-type gold ores.The results showed that the mineralization temperatures of the pyrite-quartz stage,pyrite-chalcopy-rite-quartz stage,and quartz-polymetallic sulphide stage of the vein-type gold ores in the Yixingzhai deposit are 290~300℃,(330±10)℃and(250±10)℃respectively.This result is consistent with the homogenization tem-perature of fluid inclusions in different stages of this deposit,and is more accurate,indicating that the tetrahe-drite thermometer could accurately constrain the mineralization temperature of hydrothermal deposits.