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河北蔡家营矿床是大型中温热液充填-交代脉型铅-锌-银矿床。其硫化物的δ34S值为2.2‰-7.8‰,同世代共存的10个硫化物对的Δ34S值表明,Fe-(Zn、Pb)-S系统的硫同位素非平衡分镏占主导,硫是岩浆(为主)与老变质岩层硫的混合来源。石英及其流体包裹体的δ18OSMOW和δDSMOW值(‰)按混合模式计算表明,成矿流体为混合的岩浆和大气降水,早期成矿流体以岩浆为主,尔后则变为以大气降水占优势。与方解石平衡CO2的δ13CCO2值为-3.0‰──4.8‰,表明成矿流体中的混合碳为岩浆碳和萃取自老变质岩层内大理岩的碳。矿质沉积化学环境lgfO2=-36.8──38.5,lgfS2=-10──13,pH≈5,属于硫逸度高而氧逸度较低的弱酸性还原环境。
The Caijiaying deposit in Hebei Province is a large medium-temperature hydrothermal filling-dating vein type-zinc-silver deposit. The δ34S values of sulfides range from 2.2 ‰ to 7.8 ‰. The Δ34S values of 10 sulfide pairs coexisting with each other show that the sulfur isotope imbalances of Fe- (Zn, Pb) -S systems dominate Sulfur is a mixed source of magmatic (predominant) and old metamorphic rock sulfur. The δ18OSMOW and δDSMOW values (‰) of quartz and its fluid inclusions are calculated according to the mixed model. The results show that the ore-forming fluid is mixed magma and atmospheric precipitation. The early ore-forming fluid is mainly magmatic, and then becomes predominantly by atmospheric precipitation. The δ13CCO2 value for CO2 balance with calcite is -3.0 ‰ -4.8 ‰, indicating that the mixed carbon in the ore-forming fluid is magmatic carbon and carbon extracted from marble in the old metamorphic layer. Mineral deposition chemical environment lgfO2 = -36.8 ─ ─ 38.5, lgfS2 = -10 ─ ─ 13, pH ≈ 5, belonging to a high sulfur fugacity and low oxygen fugacity of the weak acid reducing environment.