新疆乌恰萨热克砾岩型铜矿床富集规律及成矿期次

The enrichment regularity and metallogenetic period and stage of Sareke conglomerate-type copper deposit, Wuqia, Xinjiang

新疆萨热克砾岩型铜矿床是产于萨热克巴依盆地的大型铜矿床,赋矿层为上侏罗统库孜贡苏组杂砾岩,上赋层为下白垩统克孜勒苏群岩屑石英砂岩,在盆地南部白垩系地层中发育有碱性辉长岩脉。上侏罗统库孜贡苏组杂砾岩中含有大量基性火山岩砾石并伴有铜矿化。本文采用电子探针和主、微量元素分析方法对萨热克铜矿不同岩(矿)石进行研究,结合以往研究成果,总结了该矿床的富集规律,共划分为4个成矿期:晚侏罗世初始沉积成岩成矿期,白垩纪—古近纪盆地流体改造主成矿期,喜山期岩浆热液叠加成矿期和新近纪—第四纪表生作用成矿期。其中沉积成岩成矿期中的基性火山岩砾石为重要的成矿物质来源之一,可能与盆地基底中元古代阿克苏岩群有关。

In the Sarekebayi basin,Wuqia,Xinjiang,the Sareke large copper deposit hosted in glutenites of the Kuzigongsu Formation in Upper Jurassic and the upper country rocks are lithic quartz sandstone of the Kezilesu Group in Lower Cretaceous.Diabase veins are developed in the cretaceous strata in the south of the basin.The basic volcanic gravels with copper mineralition can be found in the complex conglomerate.In this paper,different rocks(ores)in Sareke copper deposit are studied by means of electron probe and maintrace element analysis.Combined with previous research results,the enrichment regularity of the deposit is summarized,which can be divided into four metallogenic periods:Late Jurassic initial sedimentary metallogenic period,Cretaceous-Paleogene basin fluid reformation metallogenic period,Himalayan magmatic hydrothermal superposition metallogenic period and Neogene-Quaternary hypergenesis metallogenic period.Among them,the basic volcanic gravel in the sedimentary diagenetic metallogenic period is one of the important sources of metallogenic materials,which may be related to the Mesoproterozoic akesu rock group in the basin basement.