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富含硫化物石英脉型金矿是加拿大太古宙金矿类型中重要的一种 .关于它的成因仍是个谜 .象 Copper Rand和 Geant Dormant这样一些金矿 ,其中的富硫化物含金石英脉的形成早于区域韧性变形 ,因而排除了变质成因的可能 .Geant Dormant金矿尤其适合于阐述金矿成因问题 ,因为其中的含金石英脉产于一层序关系保存完好的弱形变火山沉积序列中 .本文论述了与该矿床有关的火山堆积及其热液系统的演化 .从野外、岩相学与地球化学资料确定了火山演变及其形成的水下环境 .热液事件则从野外分布特征、硫化物以及蚀变矿物组合和蚀变围岩的质量平衡计算等方面加以讨论 .在分析火山与热液事件年代学和几何学关系基础上 ,认为含金石英脉是在火山成因热液系统的最后阶段形成的 ,该热液系统包括在深水火山堆积期间从贫金海底火山作用演变成富金矿脉型成矿作用的整个过程 .本文探讨了在这种环境中含金石英脉的形成和金的富集机制以及所提出的金矿成因模式在勘探中的意义 .
The genesis of sulfide-rich quartz vein-type gold deposits is an important type of Archean gold deposit in Canada, and remains a mystery. Some gold mines such as Copper Rand and Geant Dormant, in which the sulfide-rich auriferous quartz veins Formation earlier than regional ductile deformation, thus ruining the possibility of metamorphism.The Geant Dormant gold deposit is especially suitable for elucidating the gold genesis because the gold-bearing quartz veins are produced in a sequence of well-preserved weakly deformed volcanic sedimentary sequences In this paper, we discuss the volcanic accumulation and hydrothermal system evolution related to this deposit, and determine the volcanic evolution and the formation of underwater environment from the field, lithofacies and geochemical data.From the field distribution characteristics , Sulphides and alteration mineral assemblages and the mass balance calculation of alteration surrounding rocks.Based on the analysis of the chronology and geometry of volcanic and hydrothermal events, it is concluded that the Au-bearing quartz veins are formed in the hydrothermal system of volcanic origin Formed during the last stage of the hydrothermal system, which includes the evolution of a gold-bearing vein-type mineralization from the sub-sea floor to the deep-water volcano Process. This paper discusses the formation of gold-bearing quartz veins of gold in this environment and enrichment mechanism and significance of the proposed mode of Genesis of Gold in exploration.