老挝爬奔金矿床角砾岩型金矿体成因探讨

Discussion on the genesis of breccia-type gold ore body of the Phabon gold deposit, in Laos

老挝爬奔金矿矿体类型主要为角砾岩型金矿和蚀变岩型金矿,其中角砾岩型金品位较高,属于富矿段。前人认为该区赋矿角砾岩型金矿是断层角砾岩型金矿,随着采掘巷道对V-1号矿体的不断揭露,笔者观察到角砾岩呈囊状产出、围岩未变形、角砾岩内部未见明显断层角砾岩显微构造、角砾具原地破碎的可拼性特征、胶结物为热液充填物、角砾内部发育网脉状的热液充填物等不同于断层角砾岩的特征,因此提出爬奔金矿角砾岩型金矿体角砾是由于热液爆破所致,同时对热液爆破角砾岩的动力学成因进行了分析。

There are two kinds of the other is breccia-type gold ore ore bodies in Phabon gold deposit in Laos ,one is altered rock-type gold body, body which has higher gold grade. It is believed that the breccia-type gold deposit in this area related to fault. With the continuous excavation of the V-1 ore bodiy by tunnel,the author observed that all the following characteristics are different from fault breccia, such as, the breccia-type ore body is sack-like, the surrounding rock is not deformed ,and it is not found the microfracture of fault breccia, the piece of breccia can be join together, the content of cement is come from hydrothermal, the microfissure of breccia is filled by hydrothermal. So the authors consider the breccia is casused by hydrothermal blasting, and we also anal- ysis the mechanism of the breccias.