摘要
卡拉先格尔斑岩铜矿带位于我国新疆北部,大地构造位于中亚成矿域的中段、西伯利亚克拉通南缘与华北-塔里木克拉通北缘增生造山带的接合部位,夹于北西向额尔齐斯-玛因鄂博断裂带和北北西向可可托海-二台断裂带的交汇处。研究发现卡拉先格尔斑岩铜矿带在成矿构造地质、矿石组构、元素组合和成矿期次等方面表现出多期改造与叠加成矿的特征。在前期区域成矿背景、典型矿床研究的基础上,本文总结了卡拉先格尔斑岩铜矿带的构造演化与成矿过程:在中-晚泥盆世,卡拉先格尔斑岩铜矿带处于与俯冲有关的岛弧构造背景,有两期中酸性斑岩侵入与Cu-Au-Mo矿化作用;早石炭世时,区域处于碰撞造山阶段,NW向韧性剪切变形造成原斑岩中的矿化发生迁移与再定位,片理构造发育处局部得到富集;晚石炭世到二叠纪是后碰撞伸展阶段,形成了卡拉先格尔斑岩铜矿带一系列张性构造和叠加的脉状矿化;进入中生代后,常见热液脉状铜矿化充填叠加到早期矿化之上,但同时本矿带遭受强烈的抬升与剥蚀作用。
The Kalaxianger porphyry Cu ore belt in northern Xinjiang is situated on the northeastern margin of the Junggar Block, which teetonically formed in the middle part of the Central Asian Orogenic Belt. Most of the deposits in the copper ore belt underwent tectonic deformation, especially the Yuleken porphyry Cu-Mo deposit. The ore-bearing intrusive rocks in the deposit are composed of granite porphyry, granodiorite porphyry and monzogranite porphyry, which intrude into intermediate-mafic volcanic and volcanic- sedimentary rocks of the Middle Devonian and Early Carboniferous. Mylonitic deformation is common in both the ore-bearing porphyries and the wall rocks, resulting in Cu-Mo mineralisation filled along the schistosity, or along cleavage and in the chalcopyrite-K-feldspar- quartz veins. According to the previous works, the tectonic evolution and mineralization process in the Kalaxianger porphyry copper ore belt were summed up as following. Two period of medium-acidic porphyries were intruded in an island arc setting related to oceanic subduetion in the Middle-Late Devonian and accompanied by large-scale Cu-Mo mineralization; then the ore belt went deformed, relocated and enriched for copper in the NW ductile shear zone in Early Carboniferous; With the formation of Hadanxun and Mayinebo A-type granites, the superimposed Cu mineralization occurred in the post-eollisional stage in Late Carboniferous-Permian; In Mesozoic, another important superimposed mineralization was characterized by hydrothermal Cu ore veins.
出处
《岩石学报》
SCIE
EI
CAS
CSCD
北大核心
2015年第2期333-350,共18页
Acta Petrologica Sinica
基金
国家自然科学基金项目(41073037
41390445)资助
关键词
卡拉先格尔斑岩成矿带
斑岩铜矿床
改造与叠加成矿作用
构造演化
东准噶尔
Kalaxianger porphyry metallogenic belt
Porphyry copper deposit
Superimposed and reworked processes
Tectonic evolution
Eastern Junggar
