新疆和静县巴音铜矿区地质特征矿床成因及成矿模式

巴音铜矿区位于中天山中段的南缘,伊犁地块东南缘,南临南天山缝合带,处在阿吾拉勒山与那拉提山交会处,属那拉提铜、镍、金成矿带,其地质、构造特征比较复杂,成矿地质条件较为有利。通过分析区域成矿背景及矿区地质特征,总结矿床成因及控矿因素,证实该区矿化分为火山-火山热液型、脉岩型和热液脉型3种类型,就成矿机理而言,这3种矿化的形成有着密切的内在联系,在本质上都与该区晚志留世火山活动密切相关。结合区内各种矿化所占的比重和形成时间的先后顺序,其成因类型可概括为:巴音铜矿为以晚志留世海相火山-火山热液型矿化为主,伴有晚期脉岩矿化,局部受海西早期花岗质岩浆热液叠加、改造的中—低温铜矿床。不同类型矿化的主要控矿因素不同,火山岩型矿化的控矿因素主要为火山活动形式、活动阶段及岩性,同时断裂构造也有一定的控制作用;脉岩型矿化系受岩性和脉体本身(出露部位和规模)控制,较好矿化一般出现于脉岩规模较大者中,或脉岩的局部膨大部位;热液脉型矿化主要受角闪花岗岩体及其接触带控制,局部还受到后期断裂破碎带控制,矿体沿断裂破碎带充填而成。

Geological Characteristics Origin and Metallogenic Model of Bayin

Bayin copper deposit locates in the southern margin of the middle section of medium Tianshan Mountains, the southeast margin of Yili mass, and south part of the Southern Tianshan zone. It is in the intersection part of Awulale mountain and Nalati mountain, and belongs to copper, nickel, gold mineralization belt of the Nalati. Its geological, tectonic characteristics are more complex with favourable metallogenic conditions. Through analysis on regional metallogenic background and geological characteristics of mining area, origin and ore controlling factors of the deposit have been summarized. It is confirmed that the mineralization can be divided into volcanovolcano hydrothermal type, vein rock type and hydrothermal vein type. The formation mechanisms of these 3 kinds of mineralization have close relation, and have close relation with late Silurian volcano activities. Combining with the proportion of various mineralized areas and the sequence of formation time, the origin types can be summarized as: Bayin copper deposit is mainly composed of the late Silurian marine volcanovolcano hydrothermal mineralization, and accompanied by late vein rock mineralization, and regionally composed of early Hercynian granitic magmatic hydrothermal superimposition reformation, middlelow temperature copper deposit. Main controlling factors of different types of mineralization are volcano activities, activity phases and the lithology, and faults also have certain control effect. Vein type mineralization is controlled by lithology and veins itself (exposed position and scale),Good mineralization appears generally in the vein rock with large scale or in the swollen part of vein rock. Hydrothermal vein type mineralization is mainly controlled by hornblende granite and their contact parts, regionally controllded by fracture belts in the late period. Ore bodeis are formed by filling functionalong the fracture zones.