小秦岭金矿田控矿因素浅析

Analysis of ore-controlling factors in Xiaoqinling gold field

通过对河南小秦岭金矿田主要成矿地质条件的分析,分别讨论了地层、构造、岩浆岩在成矿过程中的作用。微量元素分布特征和同位素证据表明,太华群变质岩在成矿作用中提供了主要成矿物质;矿床分布规律、矿化规律均指示岩浆岩在成矿过程中提供了热动力,保证成矿物质的迁移活化,区内金成矿作用与燕山期岩浆活动的关系尤为密切。在岩浆的活化下,含矿热液沿构造迁移,当迁移到近EW向的张性构造时,温度、压力、pH等物理化学条件发生了变化,矿质沉淀并富集成矿。

Through the analysis of main metallogenic geological conditions of Xiaoqinling gold field in Henan,the paper discusses the effects stratum structure,tectonics and magmatites have on the mineralization respectively. Distribution of trace elements and isotopic evidence indicates that Taihua Group metamorphic rocks provide the main oreforming materials in mineralization; distribution of deposits and mineralization regularity indicates magmatites provide thermal power in the metallogenic process,ensuring the migration and activation of ore-forming materials. Gold mineralization in the zone is closely related to the magmatic activities in Yanshan period. In the magmatic activation,ore bearing hydrothermal fluids migrate along tectonics,and when the migration is to the EW trending tensile structures,changes happen in temperature,pressure,pH and other physical and chemical conditions,with minerals precipitating and enriched to ores.