研究矿物共生关系是揭示成矿地球化学条件的基础,是探讨矿床形成环境的一个重要方面,它对发展成矿理论起着重要作用.本文以海沟金矿为例,在广泛收集最新热力学数据的基础上,利用矿物共生关系相图初步确定了海沟金矿成矿的物理化学条件.成矿过程可分为4个阶段:石英-钾长石阶段,偏碱性(pH值7.1～9.2),弱氧化到弱还原环境(Eh值-0.3～ +0.5 V)；金-石英-黄铁矿阶段,属中酸性弱氧化-弱还原环境；金-多金属硫化物-石英阶段,中酸性(pH值4左右),弱还原环境(Eh值＜-0.2 V)；金-石英-碳酸盐阶段,从高温到低温逐步从pH=4.5转变为pH=5.3,而成矿的Eh值也从弱还原(-0.3 V)向弱氧化(+0.5 V)过渡.%The research on the relationship of mineral associations constitutes the basis of revealing metallogenic geochemical conditions and is also an important aspect in the study of the formation environment, thus having great significance for the development of the metallogenic theory. With the Haigou gold deposit as an example, the authors initially determined its physical and chemical conditions. Its metallogenic process can be divided into four stages: the stage of quartz-K-feldspar, characterized by alkaline nature (pH = 7.1~9.2) and weak oxidation environment to weak reducing environment (Eh = - 0.3~ + 0.5 V); the gold-quartz-pyrite stage, belonging to intermediate-acid weak redox environment; the gold-polymetallic sulfide-quartz stage, characterized by acid (about 4) and weak reducing environment (lower than -0.2 V); the gold-quartz-carbonate stage, characterized by the gradual transition from pH = 4.5 to pH= 5.3 with the decreasing temperature, accompanied by the transition of the metallogenic Eh value from weak reduction ( -0.3 V) to weak oxidation ( +0.5 V).
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