CAJ | 학술논문

翠宏山钨钼多金属矿床是小兴安岭张广才岭成矿带内一个重要的矽卡岩型矿床，钨、钼、锌均达大型规模。为确定该矿床的形成时代，对取自岩体内接触带钨钼矿体的7件辉钼矿样品进行了 Re Os同位素测年研究。结果表明：辉钼矿中 Re 质量分数为（0．3769～0．9737）×10-6，Os 质量分数为（1．272～3．234）×10-9；获得的模式年龄为（199．0±3．1）～（203．9±3．8）Ma，加权平均年龄为（201．6±1．4）Ma（MSWD＝0．80），等时线年龄为（198．9±3．7）Ma（MSWD＝0．83）。结合区域成矿作用分析认为：翠宏山多金属矿床的形成时代为早侏罗世，与成矿带内的霍吉河和鹿鸣等斑岩型（细网脉型）钼矿床同属燕山早期大规模构造岩浆成矿事件的产物。根据本次辉钼矿 Re Os 定年结果，结合前人在矿区内所测多个花岗岩体的锆石 U Pb 年龄认为：与翠宏山多金属矿床具成因联系的岩体应为二长花岗岩、碱长花岗岩，成岩成矿作用与古太平洋板块俯冲有关。辉钼矿中 Re 质量分数、成矿岩体的物质源区综合研究表明，翠宏山多金属矿床的成岩成矿物质具有壳幔混源特征。
취굉산오목다금속광상시소흥안령장엄재령성광대내일개중요적석잡암형광상，오、목、자균체대형규모。위학정해광상적형성시대，대취자암체내접촉대오목광체적7건휘목광양품진행료 Re Os동위소측년연구。결과표명：휘목광중 Re 질량분수위（0．3769～0．9737）×10-6，Os 질량분수위（1．272～3．234）×10-9；획득적모식년령위（199．0±3．1）～（203．9±3．8）Ma，가권평균년령위（201．6±1．4）Ma（MSWD＝0．80），등시선년령위（198．9±3．7）Ma（MSWD＝0．83）。결합구역성광작용분석인위：취굉산다금속광상적형성시대위조주라세，여성광대내적곽길하화록명등반암형（세망맥형）목광상동속연산조기대규모구조암장성광사건적산물。근거본차휘목광 Re Os 정년결과，결합전인재광구내소측다개화강암체적고석 U Pb 년령인위：여취굉산다금속광상구성인련계적암체응위이장화강암、감장화강암，성암성광작용여고태평양판괴부충유관。휘목광중 Re 질량분수、성광암체적물질원구종합연구표명，취굉산다금속광상적성암성광물질구유각만혼원특정。
The Cuihongshan deposit is one of important polymetallic deposits in the Lesser Xing’an Range Zhangguangcai Mountain polymetallic metallogenic belt.The tungsten,molybdenum and zinc resources in this deposit are over large-scale.To determine the metallogenic age of the deposit,Re Os dating of 7 molybdenite samples from W Mo ore bodies in the inner contact zone has been completed. The Re content in the molybdenite varies from (0.376 9 0.973 8)×10 -6 and Os content varies from (1.272 3.234)×10-9 .The model age of the molybdenite ranges from (199.0±3.1)Ma to (203.9± 3.8)Ma,the weighted mean age is (201.6 ± 1.4)Ma (MSWD is 0.80),and the isochron age is (198.9±3.7)Ma (MSWD is 0.83).Combined the isotopic dating with the regional mineralization characteristics,it’s suggested that the Cuihongshan polymetallic deposit be formed in Early Jurassic period,contemporary with some large-scale porphyry molybdenum deposits as Huojihe and Luming in the Lesser Xing’an Range Zhangguangcai Mountain metallogenic belt,and they are all resulted from the Early Yanshanian large-scale tectonic-magma-metallogenetic events.According to the molybdenite Re Os ages and zircon U Pb ages of some granitic rock bodies in the mine,we can conclude that the monzonite and alkali-feldspar granite were closely related to the W Mo polymetallic mineralization.The content of Re in molybdenite minerals,together with data on material source of associated intrusion, suggests that the ore-forming materials should be derived mainly from the mixing source of the crust and the upper mantle.