大兴安岭北部主要金属矿床成矿系列和区域矿床成矿谱系

Metallogenic series and ore_forming pedigree of main ore deposits in northern Great Xing'an Range

文章以大兴安岭北部内生金属矿床、海相火山岩型硫铁矿矿床和砂金矿床为研究对象,按照矿床成矿系列的学术思想将其划分为7个矿床成矿系列,即:多宝山地区与加里东期中酸性火山_侵入活动有关的铜、钼矿床成矿系列,呼玛地区与华力西期辉长岩和花岗岩有关的铁、钛、金矿床成矿系列,伊尔施_黑河地区与华力西期花岗岩和海相火山岩有关的铁、铜、锌、硫铁矿矿床成矿系列,牙克石地区与华力西期海相中基性火山岩有关的铁、锌、硫铁矿矿床成矿系列,得尔布干地区与印支期_燕山期中酸性火山_侵入活动有关的铅、锌、银、铜、钼、金矿床成矿系列,伊尔施_呼玛地区与燕山期中酸性火山_侵入活动有关的金、铁、锌、铜、钼、钨矿床成矿系列和黑龙江流域与第四纪冲积沉积作用有关的砂金矿床成矿系列。大兴安岭北部区域矿床成矿谱系表明,从奥陶纪到新生代该区不同构造单元经历了7个主要的构造演化及成矿时期,依次出现奥陶纪岛弧环境的斑岩型矿床、泥盆纪陆块边缘拉张环境的岩浆型和热液脉型矿床、泥盆纪—石炭纪俯冲_碰撞环境的海相火山岩型和矽卡岩型矿床、石炭纪弧后盆地环境的海相火山岩型矿床、晚三叠世—早白垩世俯冲_碰撞_后碰撞环境的斑岩型、热液脉型、浅成低温热液型和矽卡岩型矿床、早侏罗世—早白垩世俯冲环境的斑岩型、热液脉型、浅成低温热液型和矽卡岩型矿床和新生代地壳差异运动带砂金矿床。大兴安岭北部优势矿种为铜、钼、金、银、铅、锌,主攻矿床类型为斑岩型、热液脉型、低硫化浅成低温热液型、冲积型和海相火山岩型。

According to the theory of metallogenic series of ore deposits,seven metallogenic series for main metallic ore deposits in the northern Great Xing＇an Range have been distinguished,namely Cu and Mo deposit metallogenic series related to the Caledonian intermediate-acidic volcanic-intrusive rocks in the Duobaoshan area; Fe,Ti and Au deposit metallogenic series related to the Variscan gabbro and granite in the Huma area; Fe,Cu,Zn and pyrite deposit metallogenic series related to the Variscan granite and marine volcanic rocks in the Yirxie-Heihe area; Fe,Zn and pyrite deposit metallogenic series related to the Variscan marine intermediate-basic volcanic rocks in the Yakeshi area; Pb,Zn,Ag,Cu,Mo and Au deposit metallogenic series related to the IndosinianYanshanian intermediate-acidic volcanic-intrusive rocks in the Derbugan area; Au,Fe,Zn,Cu,Mo and W deposit metallogenic series related to the Yanshanian intermediate-acidic volcanic-intrusive rocks in the Yirxie-Huma area; and placer Au deposit metallogenic series related to the Quaternary alluviation-sedimentation in the Heilongjiang River drainage area.Study of ore-forming pedigree show that this region mainly underwent seven stages of crust evolution from the Ordovician to the Cenozoic and that corresponding seven period ore deposits were formed：the Ordovician porphyry deposits occurring in an island-arc environment; the Devonian magmaticand hydrothermal vein-type deposits occurring in an extensional environment on the margin of blocks; the Devonian-Carboniferous marine volcanic rock-and skarn-type deposits developing in a subduction to collision environment; the Carboniferous marine volcanic rock-type deposits developing a back-arc environment; the Late Triassic-Early Cretaceous porphyry-,hydrothermal vein-,epithermal-,and skarn-type deposits occurring in a subduction to post-collision environment,which was related to the Mongol-Okhotsk orogeny; the Early Jurrasic-Early Cretaceous porphyry-,hydrothermal vein-,epithermal-,and skarn-type deposits developing in a subduction environment,which was related to the northwestward subduction of the Paleo-Pacific Ocean and Izanagi plates beneath the Eurasia continent; and the Cenozoic placer gold deposits occurring in a crustal vertical movement environment.Main ore varieties are Cu,Mo,Au,Ag,Pb and Zn,and major types of ore deposits include porphyry-,hydrothermal vein-,low-sulfidation epithermal-,alluvial-,and marine volcanic rock-types.