印度尼西亚西爪哇内格拉萨金矿区古成矿流体研究

通过对比研究各种类型矿石的化学组分、矿物共生组合、围岩蚀变特征,以及包体测温数据,初步认为金在古成矿流体在中低温、低氧逸度、pH值接近中性的物理化学环境中,以硫氢络合物(Au(HS))的形式迁移。流体物理化学环境的骤变是引起矿质元素沉淀的内因;而诱发物理化学环境改变的主要外界因素是流体的沸腾作用和硫化作用。基于研究区的大地构造背景、区域成矿带及矿区地质特征,提出"本区矿床属于火山-次火山杂岩成矿体系,相应的热液系统为与火山-次火山杂岩有关的岩浆-大气降水热液系统"的假设,并利用该假设解释本区矿床的成因。

The Ancient Ore-forming Fluids Study Of NEGLASARI Mine In West JAVA,INDONESIA

In terms of the chemical composition,symbiotic mineral complexes of various ores,the characteristics of wall-rock alteration,and homogenization temperature data of fluid inclusions,it is preliminarily concluded that gold in ancient ore-forming fluids migrated as(Au(HS)-2) under the condition which is low temperature,hypoxia fugacity and pH close to neutral.The sudden change of physical chemistry condition is the essential cause that leaded gold in hydrothermal fluids to precipitation.And the outer inducement factors that caused physical chemistry environment change are primary fluids boiling and sulfuration.Based on the tectonic setting,regional metallogenic belt and geological characteristics of the mining area,one hypothesis deposit in mining area a part of a volcano-subvolcano complex metallogenic system.And the corresponding hydrothermal system is volcanic-subvocanic magma-ground water hydrothermal system is committed.It is easy to interpreter the genesis of this deposit in this mining area with this hypothesis.