高级检索

    新疆北部大地构造演化阶段与斑岩-浅成低温热液矿床的构造环境类型

    Tectonic evolution stages of northern Xinjiang and tectonic types of porphyry-epithermal deposits

    • 摘要: 提要:本文系统总结了新疆北部斑岩-浅成低温热液矿床的成矿时代,按构造环境将该类矿床归为三大类型:洋-陆俯冲型、碰撞造山型、板内型,其中碰撞造山型又可分为碰撞型和后碰撞型。4类矿床的差别主要在于矿床金属元素组合,以及同期相伴出现的矿床类型不同:俯冲型斑岩矿床以斑岩Cu-Au矿-浅成低温热液Au矿组合为主,以伴有海相火山岩有关的VMS矿床和铁矿为特征;碰撞型和后碰撞型矿床以斑岩Cu-Mo-Au组合为主,伴有构造蚀变岩型复合/叠加的浅成低温热液型Au矿出现;板内型矿床以斑岩型单Mo(或Mo-Re)组合为主。斑岩矿床与浅成低温热液矿床虽为同一成矿系统,但二者基本不共生,且后者成矿时代一般晚于前者10~20 Ma。斑岩-浅成低温热液矿床的含矿岩石和成矿特征并不随构造环境类型不同而出现特征性差别。不同时期的斑岩矿床在分布上具有继承性和“同位成矿”特点,并表现出一定的分带性,从早到晚逐渐由靠近缝合带向外扩展、由线型分布逐渐趋于面型分布。

       

      Abstract: Abstract:The metallogenic ages of porphyry-epithermal deposits in northern Xinjiang are systemically summarized in this paper. Based on tectonic setting, the ore deposits can be classified into three types, i.e., ocean-continent subduction, collision orogen composed of collision sub-type and post-collision sub-type, and intra-continent. The main differences of the four type/sub-type deposits lie in metal element assemblages of the ore deposits and the associated deposit types in the same period. Ocean-continent subduction type porphyry deposits are mainly characterized by Cu-Au association, accompanied by VMS deposits as well as iron deposits related to submarine volcanism; collision type deposits and post-collision type deposits are characterized by Cu-Mo-Au association, accompanied by orogenic gold deposits; intra-continent type deposits are characterized by single metal element Mo (or Mo-Re association). Porphyry deposits and epithermal deposits belong to the same metallogenic system, but they do not coexist, and metallogenic age of the latter is later than the former by about 10Ma to 20Ma. The host rocks and metallogenic characteristics of different types of porphyry-epithermal deposits don’t show symbolic difference. Porphyry deposits in different metallogenic epochs show genetic and regional “isospatial metallogenesis” characteristics and zoned distribution; from early to late the deposits expanded gradually from the position close to the suture belt outwards, and from linear distribution to planar distribution.

       

    /

    返回文章
    返回