【摘要】 上宫金矿是典型的断控脉状造山型金矿床,成矿过程包括早、中、晚3个阶段。蚀变岩和矿石的δ18O明显高于未蚀变岩石,指示岩石在水岩作用过程中从流体中汲取18O。19件早阶段流体δ18OW变化于4.2‰～13.4‰(平均8.1‰),8件δDW介于-66‰～-88‰之间(平均-78‰),1件δ13C铁白云石=1.5‰,指示流体来源于含碳酸盐地层的变质脱水作用;晚阶段δ18OW为-2.0‰～-0.6‰,1件δDW=-56‰,3件δ13C铁白云石为-1.6‰～-2.2‰,指示流体以大气降水为主要成分;3件中阶段样品δ18OW为1.9‰～4.5‰,δ13为-1.2‰～0.5‰,均介于早、晚阶段之间,指示中阶段为变质热液与大气降水热液的CCO2混合流体作用。大量硫化物沉淀导致中阶段流体(δDW=-113‰～-94‰),显著低于早、晚阶段。28件中阶段硫化物δ34S为显著的负值(-19.2‰～-6.3‰),指示成矿流体系统中存在大量生物硫。理论分析表明,尽管熊耳地体的太华超群、熊耳群、燕山期花岗岩类和下伏地壳、地幔被前人解释为成矿流体的来源,但它们之一或其任意比例的混合物均不可能成为上宫金矿成矿流体的主导性物源,唯一可能是熊耳地体南侧的管道口群-栾川群CSC(含碳质碳酸盐-页岩-硅质岩)建造;在中生代华北与扬子板块的碰撞造山过程中,管道口群-栾川群沿马超营断裂A型俯冲到熊耳地体之?更多还原

【Abstract】 The Shanggong Au deposit is a typical fault-controlled orogenic-type lode gold deposits. Its ore-forming process includes the early, middle and late stages. The δ¹⁸O values of ores and altered rocks are higher than those of unaltered rocks, suggesting that the rocks have extracted （）¹⁸O from fluids during fluid-rock interaction. Nineteen δ¹⁸O_W values, ranging from 4.2‰¹3.4‰ and averaging 8.1‰, eight δD_W values, ranging from -66‰^-88‰ and averaging -78‰ and a δ¹³Cankerite value （1.5‰）, suggest that the early stage fluids derived was from metamorphic devolatilization of carbonate-bearing strata. As for late stage, three δ¹⁸O_W values,ranging from -2.0‰^-0.6‰, a δD_W value （-56‰）, and three δ¹³C_ankerite,ranging from （-1.6）‰^-2.2‰, show that the fluids were dominated by meteoric water. Three middle stage samples yield δ¹⁸O_W values of 1.9‰⁴.5‰ and δ¹³C_CO2 values of -1.2‰⁰.5‰, exactly between the values of the early and late stages. This strongly indicates that the middle stage was characterized by a mixing phase of metamorphic and meteoric fluids. The δD_W values for middle stage range from -113‰ to -94‰, lower than those of the early and late stages, which can be interpreted as being resulted from large-scale precipitation of sulfides. 28 negative δ³⁴S values for the middle stage sulfides （-19.2‰ to -6.3 ‰） suggest a contribution of biogenic matter to ore-forming fluid-system. Theoretical synthesis shows that none of the main geologic units in the Xiong′er Terrane, i.e. the Taihua Supergroup, the Xiong′er Group and the Yanshanian granitoids, and the underlying lower crust and the mantle,could be considered as the source of ore fluids for the Shanggong Au deposit,although it was suggested in previous studies. Instead, a source which meets the isotopic constraints, is a carbonaceous carbonate-sandstone-shale-chert （CSC） sequence in the Guandaokou and Luanchuan Groups in the south of the Xiong′er Terrane. During the Mesozoic collision between the Yangtze and North China continents, the Guandaokou and Luanchuan Groups underthrusted beneath the Xiong′er Terrane along the north-dipping Machaoying A-type subduction zone, and then devolatilized through metamorphism,leading to the development of the Shanggong ore-forming fluid-system. Therefore,the CMF （collisional orogeny, metallogeny and fluid flow） model could be applied to the interpretation of the hydrothermal metallogenesis of the Shanggong Au deposit.更多还原