CAJ | 학술논문

大峡铜金矿床位于中秦岭前陆盆地构造区,即西秦岭北部断褶带与中部裂陷槽之间的过渡部位,属于典型的秦岭复合型大陆碰撞造山带的组成部分.矿体呈扁豆体状或透镜体状产出于闪长岩岩体围岩接触带的矽卡岩带内及闪长岩岩体内部张性裂隙中,矿石中金属矿物主要为黄铁矿、黄铜矿.黄铁矿为主要的载金矿物,矿石以块状、星散浸染状、脉状构造为主.对与成矿有关的闪长岩样品中锆石的12个测试点用 SHRIMP 锆石 U -Pb 法得出206 Pb/238 U 加权平均年龄值为(219.1±2.1)Ma,表明闪长岩成岩时代为中—晚三叠世的印支末期,岩体形成于印支末期中酸性岩浆活动.结合矿床地质特征和前人的研究成果认为,大峡铜金矿床具有造山型金矿床的成矿特点,为与印支末期造山作用有关的矽卡岩型—石英脉型铜金矿床.
대협동금광상위우중진령전륙분지구조구,즉서진령북부단습대여중부렬함조지간적과도부위,속우전형적진령복합형대륙팽당조산대적조성부분.광체정편두체상혹투경체상산출우섬장암암체위암접촉대적석잡암대내급섬장암암체내부장성렬극중,광석중금속광물주요위황철광、황동광.황철광위주요적재금광물,광석이괴상、성산침염상、맥상구조위주.대여성광유관적섬장암양품중고석적12개측시점용 SHRIMP 고석 U -Pb 법득출206 Pb/238 U 가권평균년령치위(219.1±2.1)Ma,표명섬장암성암시대위중—만삼첩세적인지말기,암체형성우인지말기중산성암장활동.결합광상지질특정화전인적연구성과인위,대협동금광상구유조산형금광상적성광특점,위여인지말기조산작용유관적석잡암형—석영맥형동금광상.
Hezheng Daxia copper-gold deposit locates in foreland basin structure area of middle Qinling Mountains,i.e.the transition part between the fracture fold belt of northern west Qinling Mountains and the collapsed geosyncline of middle-west Qinling Mountains,belonging to a part of typical Qinling complex collisonal orogenic belt . The pisolitic and lenticular orebody occurs in skarn belt that distributes in contact zones linking dioritic rock with country rock and within the tensile fractures inside dioritic rock .Pyrite and chalcopyrite are the main metallic mineral composition in ore.Pyrite is the main carrier of gold mineral,taking form of block structures,scattered,disseminated structures and vein structures .Based on the U -Pb dating of zircon by SHRIMP on 12 test points of zircons from a di-oritic sample that is related with the metallogenic process ,a weighted average 206 Pb/238 U age of (219.1 ±2.1)Ma was obtained,showing that the dioritic diagenetic era was in end indosinian age of middle -late Triassic.The rock mass orig-inated in acid magmatic intrusive movement in end Indonisian movement period .Associating geological characteristics of ore deposit and predecessors'research,the paper considers that there are geological features of orogenic gold depos -its in Hezheng Daxia copper-gold deposit and the deposit is a skarn -quarts vein type copper-gold deposit that is related to orogeny in end Indonisian period .