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长坑矿床金、银矿石硫化物的δ ̄(34)S分别以高离散的负值和相对较集中的正值为特征。在主要成矿阶段硫同位素基本达到平衡或近平衡分馏条件下,采用大本模式分析表明,硫同位素分布特征可能与成矿流体物理化学条件不同有关,即形成金矿石的热液偏酸性、f_o_2效高.而银矿化期的流体近中性、f_o_2较低:此外,伴随硫化物沉淀的储库效应对此也有一定的影响。热液的总硫同位素组成可取为4‰─7‰,应主要来自围岩中的沉积硫。成矿机制包括流体混合、氧化作用、水一岩反应。
The δ ~ (34) S of gold and silver ores in Changkeng deposit are characterized by high discrete negative values and relatively concentrated positive values, respectively. Under the conditions that the sulfur isotopes basically reach balance or nearly equilibrium fractionation in the main metallogenic stage, the analysis of large - scale model shows that the distribution characteristics of sulfur isotopes may be related to the different physicochemical conditions of ore - forming fluids, ie, the hydrothermal partial acidity of gold ore, f_o_2 High efficiency. In the silver mineralization phase, the fluid is near neutral and f_o_2 is low. In addition, the reservoir effect associated with sulfide precipitation also has some influence on this. The total sulfur isotopic composition of hydrothermal fluids is desirably from 4 ‰ to 7 ‰ and should mainly come from the deposition of sulfur in the surrounding rock. Mineralization mechanisms include fluid mixing, oxidation, water-rock reaction.