平顶山金矿床位于佳木斯地块东北部,矿床的产出受断裂构造控制,矿体主要赋存于高角度张性破碎带中,矿石类型为石英脉和蚀变岩两种.笔者在对平顶山金矿的成矿地质背景、矿床地质特征详细研究基础上,通过对各成矿阶段代表性的原生流体包裹体进行岩相学观察、显微测温和激光拉曼探针分析,探讨了成矿流体性质和矿床成因类型.流体包裹体研究表明,流体包裹体以气液两相为主.主成矿阶段流体均一温度具有中低温(142.2℃~267.3℃)、低盐度(1.90% ~4.32% NaCl)、低密度(0.81 ~0.94g/cm3)的特征.包裹体气相成分主要为H2O,其次为CH4和CO2,液相成分主要为H2O和CH4.综合研究表明,平顶山金矿属于受断裂控制的中低温热液脉型金矿床.
Pingdingshan gold deposit was located in the northeast of Jiamusi block,controlled by faults.And ore-bodies occurred in the tensional high-angle fractured-altered zone.The ore includes of the quartz-vein type and altered rock type.On the basis of the detailed study of its mineralization geological background and characteristics,the authors discussed the property of metallogenic fluids and deposit type through petrography,micro thermometry and Raman microprobe of represented samples.The results showed that fluid inclusions in quartz were well developed mainly in gas-liquid phase.The fluid of main ore-forming phase was characterized by medium-low temperature (142.2 ~ 267.3 ℃),low salinity (1.39 ~ 5.25 % NaC1) and low density (0.78 ~ 0.97 g/cm3).The gas phase composition of the ore-forming fluid mainly were H2O,CH4and CO2,while the liquid phase were H2O and CH4.Comprehensive study showed that the Pingdingshan gold deposit belonged to the gold deposit of medium-low temperature hydrothermal vein type.