若尔盖碳硅泥岩型铀矿成矿规律及控矿因素分析

西秦岭南亚带的若尔盖碳硅泥岩型铀矿床是中国重要的十大铀资源基地之一,但是在加大找矿深度、扩大资源量以及矿床成因等方面仍然存在一系列的问题。通过多年的详实野外勘查和研究,总结出了若尔盖地区硅泥岩型铀矿的矿体形态、产出特征及空间分布规律,即矿床主要产于下志留统一套浅变质硅质岩、灰岩、板岩层中,矿体形态呈似层状、透镜状、扁豆状,矿体严格受岩性、构造、硅灰岩组合体3要素控制; 提出了“断裂构造-硅灰岩组合体-岩性界面”3要素组合控矿的成矿规律,以及“组合成矿”和“深源流体”对若尔盖铀成矿起主导作用的新认识。

Metallogenic Regularities and Ore Controlling Factors of Carbonaceous- Siliceous-Pelitic Rock Type Uranium Deposits in Zoige

The Zoige carbonaceous-siliceous-pelitic rock type uranium deposits locate at the south subzone of western Qinling Mountains, which is one of the ten largest uranium resource bases in China. However, some problems still need to be answered, such as deep exploration, resource expansion and ore genesis. The shape, occurrence and distribution for ore bodies of Zoige carbonaceous-siliceous-pelitic rock type uranium deposits are summarized according to detailed field investigation and research in recently years. These layered, lenticular and lentil ore bodies mainly occur in Silurian low metamorphic siliceous rocks, limestone and slate, and these ore bodies are controlled by lithology, structure and siliceous limestone. It is proposed that the three essential ore controlling factors are fault structure, siliceous limestone and lithological boundary. It is inferred that the superimposed mineralization and deep fluid have important role in the formation of uranium deposits of Zoige area.