梅河口市香炉碗子金矿床地质及地球化学特征.docVIP

梅河口市香炉碗子金矿床地质及地球化学特征 　　【摘 要】 论文在以往勘查和科研成果基础上，总结了矿区地层、构造、岩浆岩以及矿体的空间分布、矿化蚀变等矿床地质特征，归纳了微量元素、稀土元素、硫同位素、氢氧同位素、铅同位素及锶同位素地球化学特征，进而总结了矿床的成矿物质来源和成矿时代。成矿物质及成矿流体具有多来源性，携带成矿物质的多来源成矿流体在物化条件突变的构造有利部位，Au被卸载，富集成矿。成矿作用发生于124Ma～157Ma，与燕山晚期构造岩浆活动事件有关。 　　【关键词】 矿床地质特征 地球化学特征 成矿物质来源和成矿时代 　　【Abstract】 In this paper， on the basis of previous exploration and research achievements， we summarized the geological characteristics of ore deposits including the formation， structure， spatial distribution of magmatic rocks and ore bodies， and mineralization alteration of the Xiangluwanzi Gold Deposit. Furthermore， the geochemical characteristics including trace elements， rare earth elements， and isotope information of sulfur， hydrogen-oxygen， lead and strontium of the minerals and rocks were also reviewed. It can be concluded that the sources of metallogenic material and metallogenic epoch for ore deposit as the following： The ore-forming material and ore-forming fluids were provided with multiple sources. At the tectonic locations with the physicochemical conditions drastically changed，the element Au in these ore-forming fluids with enrichment of ore-forming material was hold up and concentrated into the gold deposit. This mineralization was related to the tectonic-magmatic activity in the late Yanshanian which is aged 124Ma～157Ma. 　　【Key words】 the geological characteristics of ore deposits；the geochemical characteristics ；the sources of metallogenic material and metallogenic epoch for ore deposit 　　1 矿床地质特征 　　矿区大地构造位置位于胶辽吉叠加岩浆弧（Ⅱ）吉南―辽东火山-盆地群（Ⅲ）柳河―二密火山―盆地区（Ⅳ），NE向柳河断裂与NW向水道―香炉碗子西山断裂交叉部位[1]。 　　1.1 地层特征 　　矿区内主要分布太古界杨家店组古老变质岩系的黑云―角闪斜长片麻岩及黑云变粒岩，局部夹磁铁矿，原岩为一套超基性―中基性海底火山喷发建造；矿区的东南部边缘分布有中―晚侏罗世的杂色砂砾岩、凝灰岩，流纹岩等火山岩，原岩为一套陆相碎屑―火山建造。见图1。 　　1.2 构造特征 　　矿区内以北东向脆-韧性剪切带横贯全区为特点，EW和NE向断裂构造为主，也是本区的主要控矿构造。其次为近SN和NW向断裂，见图1。烟囱桥子-龙头EW向脆-韧性剪切带主要发育在杨家店组地层内。剪切带内片糜岩、糜棱岩、初糜岩和糜棱岩化发育，被不同期次的岩体和脉岩充填。该剪切带控制了侵位时间和岩性相同、呈脉状或岩墙状的东山、西山、荷包褶子和烟囱桥子隐爆角砾岩体的空间分布。由于该构造带的多期次活动，造成不同期次的构造岩浆活动的叠加，使围岩中的成矿物质不断活化、迁移和富集，与来自岩浆中的成矿物质共同在构造的有利部