摘要
金家庄金矿床矿体主要赋存在超基性岩体内的断裂带及超基性岩体与围岩的接触带附近的蚀变破碎带中。矿石类型以蚀变辉石岩型金矿石为主。主要矿石矿物为银金矿、自然金、黄铁矿、方铅矿等。同位素分析结果表明,成矿溶液的碳同位素组成为δ^(13)C=-2.8‰～-7.6‰,硫同位素组成为δ^(34)S=+2‰。碳、硫均属于慢源型,主要来自超基性岩体。矿石铅同位素组成显示出混合铅特征,主要由地幔铅与少量的下部地壳铅混合而成。说明金属铅及其它成矿元素主要由其赋矿围岩(超基性岩体)所提供。
Jinjiazhuang gold deposit is situated at the north margin of North China Plateform. The ore bodies mainly occur in the fissures of Xiaozhangjiakou ultrabasic instrusion and the Country rocks near the contact zone. The ores are primarily the type of alterated pyroxenite and in quartz vein. The metal minerals indude pyrite, galena, electrum, native gold, goldschmidtine etc. Carbon and Sulfur isotopic compositions of ore-forming solution are δ ^(13)C=-2.8 ^-7.6‰, δ^(34)S=+2‰. It is illustrated that Carbon and Sulfur are mantle- derived, primarily coming from the ultrabasic rocks. Lead isotopic compositions of gold ore show the feature of mixed lead. Most of them are mantle-derived lead, less of them being derived from lower crust. It is indicated that lead and other metallogenic elements mainly come from the host rocks-Xiaozhangjiakou ultrabasic instrusion.
