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对鲁西平邑地区归来庄金矿成矿晚阶段蚀变矿物方解石的流体包裹体和稳定同位素进行了详细的研究后发现:保存于方解石脉中的包裹体均为气液两相盐水溶液,均一温度在110℃～250℃之间,冰点变化于-2.8℃～-9.3℃之间,对应的盐度在4.65%～13.18%之间。同位素研究结果显示:矿床的δ34S值介于-0.71‰～2.990‰之间,δ13CPDB值为-3.3‰～0.0‰,δDSMOW为-48‰～-61‰,δ18O水值在-1.13‰～5.07‰之间。硫同位素研究表明成矿流体来源于地幔,碳、氢、氧同位素则显示有较多的大气降水混入。锆石SHRIMP测年结果暗示归来庄金矿形成于中侏罗世,其成因与角砾岩体的隐爆、流体的减压沸腾和深循环的古大气水混入有关。
The fluid inclusions and stable isotopes of the altered minerals calcite in the late stage of the ore-forming of the Guolaizhuang gold mine in the Pingyi area are studied in detail. It is found that the inclusions in the calcite veins are both gas-liquid two-phase brine solution, The temperature is between 110 ℃ ~ 250 ℃, the freezing point changes between -2.8 ℃ ~ -9.3 ℃, the corresponding salinity is between 4.65% ~ 13.18%. The results of isotope studies show that the δ34S value of the deposit is between -0.71 ‰ and 2.990 ‰, the δ13CPDB value is -3.3 ‰ to 0.0 ‰, the δDSMOW is -48 ‰ to -61 ‰ and the δ18O water value is -1.13 ‰ to 5.07 ‰ between. Sulfur isotope studies indicate that the ore-forming fluid is derived from the mantle, while carbon, hydrogen and oxygen isotopes show more mixed precipitation. The zircon SHRIMP dating results suggest that the Guolaizhuang gold deposit was formed during the Middle Jurassic. The origin of the Gulaizhuang gold deposit is related to the cryptoexplosion of breccia bodies, the decompression boiling of fluids and the deep circulation of paleo-atmospheric water.