摘要
热力学计算表明,金主要以Au(HS)_2^-络合物形式迁移,Au(HS)_2^-的活度达2.43×10^(-6)(m)(金-石英阶段)和1.46×10^(-6)(m)(金-石英-硫化物阶段)。硅化作用、硫化物化作用、菱铁矿化作用以及磁黄铁矿与黄铁矿的转变作用,引起流体fo_2和pH的降低,含金络合物发生分解,金得以沉淀。此外,含金络合物与围岩中铁的反应也是造成金沉淀的重要原因之一。
Thermodynamic calculations show that gold was transported mainly as Au(HS)_2^- complex. Theactivity of Au(HS)_2^- is 7.7×10^(-8)(m) for the gold-quartz stage and 1.46×10^(-6)(m) for the goldquartz-sulfide stage. Gold-complex decomposed and gold deposited in. response to the decrease of fo_2and pH that was caused by siliconizing, sulfidization, sideritization and the conversion of pyrrhotiteinto pyrite. Furthermore, it is one of the important reasons for the deposition of gold that gold com-plexes react with Fe in wallrock.
出处
《地质找矿论丛》
CAS
CSCD
1991年第3期40-45,共6页
Contributions to Geology and Mineral Resources Research
