新疆北部浅成低温热液金矿地质特征

GEOLOGY OF EPITHERMAL GOLD DEPOSITS IN THE NORTHERN XINJIANG

新疆北部浅成低温热液型金矿主要产在碰撞造山带拉张环境浅海相、海陆交互相地层内，是长期多次热液活动的结果。控矿条件受火山机构断裂构造的控制，成矿时间跨度大。火山机构断裂既是导矿构造又是容矿构造。成矿岩石为一套钙碱系列和碱性系列的中酸性火山岩。成矿时代为２４４～３４０Ｍａ。成矿元素组合主要为Ａｕ、Ａｇ、Ｈｇ、Ａｓ、Ｓｂ、Ｂｉ。稳定同位素、包裹体研究表明，成矿热液主要来源于岩浆和大气降水，金矿物质来源于火山岩。

The epithermal gold deposits in the northern Xinjiang are hosted in marine and marine continental strata which were deposited under extensional environment of collision orogenesis. These gold deposits are controlled by faults related to edifice. The wide span of metallogenic time indicates that they resulted from long active hydrothermal processes. The passage way for ore fluid and host structures are represented by these fractures related to edifice. The ore bearing rocks are considered to be mediate acidic volcanics of calcic alkaline series. The gold deposits were formed at 244Ma～340Ma with elementary assemblage of Au, Ag, Hg, As, Sb, Bi. It is confirmed by isotopes and inclusions that the fluid was derived from magmatic water and meteoric water, and that the ore forming materials from volcanics.