金矿成矿流体特点及深-浅部流体相互作用成矿机制  

CHARACTERISTICS OF GOLD ORE-FORMING FLUIDS AND METALLOGENIC PROCESS BY MUTUAL MIXING AND ACTING OF DEEP-DERIVED FLUIDS AND SHALLOW-SEEPED ONES

作　　者：胡文宣[1] 孙睿[1] 张文兰[1] 孙国曦[1] 

机构地区：[1]南京大学地球科学系内生金属矿床成矿机制研究国家重点实验室,江苏南京210093

出　　处：《地学前缘》2001年第4期281-288,共8页Earth Science Frontiers

基　　金：国家自然科学基金资助项目 ( 499730 0 1;4973312 0 )

摘　　要：以中国一些典型金矿研究资料为基础 ,结合前人关于深部流体研究成果 ,分析对比了金矿成矿流体和深部流体的特点 ,总结了深部流体参与金矿成矿作用的主要表现 ,然后计算了深部富气流体的能量传递效应和富水流体在不同深度上的密度变化规律。认为深部富气流体主要是向浅部输送大量热能和部分有利于成矿的物质 ,而浅部富水流体下渗提供足够的水体 ,二者在中地壳的“低速层”附近交汇 ,发生相互作用并作用于围岩 ,在有利条件下演化形成成矿流体 ,最终上升到地壳浅部沉淀成矿。Based on the data taken from the typical gold deposits in China and literatures about deeply derived fluids, analysis and comparison are carried out on the characteristics of and relationship between the gold ore forming fluids and deeply derived ones. By using the equation of state for geofluids, the enthalpy and densities of the systems of H 2 O and H 2 O CO 2 are calculated. The enthalpy results show that the deeply derived fluids contain substantial energy, which could largely provide heat to the shallowly seated fluids, as well as some useful materials for metal enrichment. And the density profiles illustrate that the densities of H 2 O rich fluids at shallow depth are relatively heavier than that at deeper depths, which could make the H 2 O rich fluids seep down to relatively deep depths of about 15～30 km. Therefore, the water rich fluids seeped down from shallow and the gas rich fluids derived from deep could meet and get mixed each other at that depths, resulting in various physico chemical and geochemical processes, and even leading to ore forming fluids under favorable conditions, which is believed to be a very important metallogenic mechanism for the gold deposits.

关 键 词：金矿成矿流体 深部流体 浅部流体 相互作用 成矿机制 金矿床 成矿作用 

分 类 号：P618.51[天文地球—矿床学]