热液条件下Au 络合物迁移行为的热力学模拟计算  

Thermodynamic Simulation of Migration Behavior of Au Complex Under Hydrothermal Conditions.

作　　者：马璐瑶 马勋娇 MA Lu-Yao;MA Xun-Jiao(School of Earth Sciences,East China University of Technology,Nanchang 330013,Jiangxi,China)

机构地区：[1]东华理工大学地球科学学院,江西南昌330013

出　　处：《华南地质》2025年第1期75-85,共11页South China Geology

基　　金：东华理工大学研究生创新基金(DHYC-202407)。

摘　　要：金矿床的形成主要依赖于成矿热液将地下深部金元素运移至地壳浅部并促使其沉淀、富集,该过程在很大程度上取决于金络合物在热液环境中的稳定性。深入探究富金流体形成与迁移的具体条件,关键在于明晰影响热液中金络合物稳定性的物理化学因素。本文以热力学理论为基础,对地球化学模拟软件GEM-Selektor的数据库进行补充后,按照自然热液环境设计了不同的流体体系,并对其进行金的溶解度计算。研究结果表明,热液流体若呈现高温状态,同时具有较高的氧逸度,并富含HS^(−)和S_(3)^(−)等还原性硫配体时,将更有助于金的溶解。Au-HS^(−)络合物相较于Au-Cl−络合物展现出更高的稳定性,尤其是Au(HS)S_(3)^(−)的存在,显著提升了成矿流体在演化阶段萃取金的能力及运输效率。The formation of gold deposits mainly depends on the transport of gold elements from deep underground to shallow crust by ore-forming hydrothermal fluids and their precipitation and enrichment,a process that largely depends on the stability of gold complexes in hydrothermal environments.The key to exploring the specific conditions for the formation and migration of gold-rich fluids is to clarify the physicochemical factors that affect the stability of gold complexes in the hydrothermal fluids.Based on the thermodynamic theory and after the supplementary database of the geochemical simulation software GEMSelektor,different fluid systems are designed according to the natural hydrothermal environment,and the gold solubility calculations are carried out in this study.The results show that hydrothermal fluids with high temperature,high oxygen fugacity,and rich in reducing sulfur ligands,such as HS^(−)and S_(3)^(−)are more conducive to gold dissolution,and that Au-HS^(−)complexes exhibit higher stability than Au-Cl−complexes,especially the presence of Au(HS)S_(3)^(−),which significantly enhances the extraction capacity and transport efficiency of gold in the evolutionary stage of the ore-forming fluids.

关 键 词：地球化学 热力学模拟 金络合物 热液流体 

分 类 号：P595[天文地球—地球化学] P618.51[天文地球—地质学]