CAJ | 학술논문

内蒙古自治区锡林郭勒盟西乌旗道伦达坝中型铜多金属矿床位于大兴安岭南段西坡,矿体主要产于粉砂质板岩与黑云母花岗岩的接触带.本文通过系统的岩相学、矿相学、流体包裹体和氢、氧同位素研究表明,道伦达坝铜多金属矿床属岩浆期后气化热液矿床,成矿过程包括早、中、晚3个阶段,温度区间分别为388～＞500℃、302～463℃、179～359℃.钨-锡矿化主要发生在中阶段、铜矿化主要发生在晚阶段.初始成矿流体为CH_4-CO_2-H_2O-NaCl体系,随着温压降低,CO_2、CH_4大量逸失,而演化为H_2O-NaCl体系.流体盐度变化范围大,但从早到晚逐步降低.流体临界分离导致钨、锡矿化;流体CH_4、CO_2逃逸和大气降水热液混入导致铜矿化.黑云母花岗岩的侵入活动导致了成矿流体的聚集,而粉砂质板岩有利于成矿流体封闭,致使二者接触带成为有利的成矿和找矿部位.
내몽고자치구석림곽륵맹서오기도륜체패중형동다금속광상위우대흥안령남단서파,광체주요산우분사질판암여흑운모화강암적접촉대.본문통과계통적암상학、광상학、류체포과체화경、양동위소연구표명,도륜체패동다금속광상속암장기후기화열액광상,성광과정포괄조、중、만3개계단,온도구간분별위388～＞500℃、302～463℃、179～359℃.오-석광화주요발생재중계단、동광화주요발생재만계단.초시성광류체위CH_4-CO_2-H_2O-NaCl체계,수착온압강저,CO_2、CH_4대량일실,이연화위H_2O-NaCl체계.류체염도변화범위대,단종조도만축보강저.류체림계분리도치오、석광화;류체CH_4、CO_2도일화대기강수열액혼입도치동광화.흑운모화강암적침입활동도치료성광류체적취집,이분사질판암유리우성광류체봉폐,치사이자접촉대성위유리적성광화조광부위.
The Daolundaba medium-sized Copper-poly-metal deposit in Xiwuzhumuqin Qi,Xilinguole City,Inner Mongolia,occurs in the western Great Xing'an Range.Ore-bodies are mainly hosted in the contact zone between a biotite granite and a silty slate.The study in ore petrography and fluid inclusions and hydrogen oxygen isotope geochemistry shows that the Daolundaba deposit was formed by post-magmatic hydrothermaI process.Hydrothermal mineralization are divided into the early,middle and late stages with homogenization temperatures of 388～＞ 500℃,302～463℃ and 179～359℃,respectively.W and Sn mineralization occurred in the middle stage,while the Cu mineralization mainly occurred in the late stage.The ore-forming fluid was originally a CH_4-CO_2-H)_2O-NaCl system,and evolved into a H_2O-NaCl system through release of CH_4 and CO_2 along with decreasing temperature and pressure.The fluid salinity was widely variable,but decreased from early to late.The vapor-brine phase separation resulted in mineralization of W and Sn;and the CH_4 and CO_2 escape and the input and mixing of meteoric water caused Cu deposition.During the hydrothermal mineralization,the biotite granite wall-rock and silty slate served as seal and container to trap ore-fluids,respectively.This makes the granite-slate contact zones to be key positions for metallic mineralization and future ore exploration.