贵州晴隆大厂锑矿床控矿条件及成矿机制

Ore-Controlling Conditions and Ore-Forming Mechanism of the Dachang Antimony Deposit in Qinglong, Guizhou Province

贵州晴隆大厂锑矿床是一个层控型火山沉积—后期改造矿床。控矿条件是;①一定层位控制:大厂地区锑矿体及矿化点均产在“大厂层”中。矿源层是“大厂层”,锑来源于地幔,与玄武岩关系密切。“大厂层”形成的环境是河口湾相,与茅口组为连续沉积。②岩性控制:锑矿主要产在“大厂层”中段硅化粘土岩中,特别是硅化粘土岩与下段石英蚀变岩接触部位上。部分产在“大厂层”上部变余玄武岩中,少部分产于下段石英蚀变岩中。③构造控制:大厂锑矿主要产在黑山箐—后坡背斜的轴部、高点、次高点及翼部次级鼻状构造、挠曲以及断层造成的牵引褶曲内。分布地域受花鱼井断层和青山镇断层的控制,因此,两条断层之间的地域是找矿的有利区段。

The Dachang Antimony Deposit in Qinglong, Guizhou, is that of horizon - controlling type volcanic sedimentation-transformation in the later period. The ore-conditions are as follows: 1. Controlled by certain horizons : Antimony ore bodies and mineralization points in Dachang area all occur in Dachang Horizon which means antimony ore source bed, with antimony derived from the mantle closely related to basalt. The formation environment of Dachang Horizon belongs to estuarine fades deposited successively with Maokou Formation. 2. Controlled by lithological features: Antimony ore occurs mainly in silicified clay rocks and quartz altered rocks in the lower part of Dachang Horizon. Some antimony ore occurs in blastobasalt in the upper part of Dachang Horizon and only a small amount of antimony ore occurs in quartz al tered rocks in the lower part of Dachang Horizon. 3. Controlled by Structures: The Dachang Antimony Deposit is mainly distributed in Heishan-qing-Houpo anticline controlled by Huayujing and Qingshanzheng faults between which antimony ore can be prospected.