In this paper,based on analysis of 1572 small and above scale gold deposits in China,the gold deposits,for prediction purposes,are divided into four types:the sedimentary,volcanic rock,magmatic hydrothermal and shear zone type.The spatial and temporal distribution of gold deposits in China is nonuniform as 60％ of deposits distribute in the land block,and Mesozoic deposits account for 71.5％ of the national total.It is found that intrusive and sub volcanic rocks are the main ore-forming geological bodies;here the method for accurately identifying spatial positions of concealed rocks is summarized.Through the geological profile study of 450 representative gold deposits,the paper suggests that there are mainly two kinds of gold deposits in China.One is characterized as Au and Ag associated,with formation temperatures around 250 ℃;it has very low As and Sb contents;fineness of gold is generally below 900;and unequal strength Kfeldsparization and albitization formed in the early stage.The other is Au,As and Sb associated;formation temperatures are below 250 ℃;fineness of gold is generally higher than 900;it has low Ag and high As and Sb contents;and alteration was mainly in the form of silicon with some secondary quartz formed in the early mineralization stage.Taking into account elemental geochemical characteristics,the mechanism of gold migration and precipitation in the transient transition process from fluid to solid minerals in the ore forming structure is discussed.It provides a reference for future gold prospecting.%在系统分析研究中国1572座小型及以上规模金矿床资料的基础上,以找矿预测为目的,根据成矿地质作用类型划分了沉积型、火山岩型、岩浆热液型和剪切带型金矿4种类型.提出了中国金矿床空间分布不均衡性和成矿时代爆发性特点:陆块区分布的金矿床占全国总金矿数的60％,中生代金矿占全国总金矿数的71.5％.研究发现侵入岩和次火山岩是金矿床最主要的成矿地质体,并总结了识别隐伏岩体空间位置的方法.通过对450座代表性金矿床地质事实的统计研究,提出中国金矿主要为两类:一类金矿床Au和Ag共伴生,成矿温度约250℃,Au的成色一般低于900,As和Sb含量极低,成矿早阶段形成强度不等的钾长石化、钠长石化;另一类金矿床Au和As、Sb共伴生,成矿温度低于250℃,Au的成色一般高于900,Ag含量低,成矿早阶段蚀变主要为硅化,有的为次生石英岩.以元素地球化学特征作为切入点,探讨了金从流体组分转变为成矿结构面中的固体矿物组分这一短暂过程的迁移沉淀机制,为金矿的找矿提供了借鉴依据.
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