内蒙古太平川钼铜矿床岩石地球化学、热液活动记录与年代学  

Petrogeochemistry,records of hydrothermal activities and geochronology of the Taipingchuan Mo-Cu Deposit,Inner Mongolia

作　　者：王召林[1] 李占龙[1] 郑小明[1] 

机构地区：[1]有色金属矿产地质调查中心,北京100012

出　　处：《矿产勘查》2017年第2期184-195,共12页Mineral Exploration

基　　金：国家科技支撑计划资助项目(编号:2006BAB01A10);中国地质调查局地质矿产调查项目(编号:12120115030901)联合资助

摘　　要：太平川钼铜矿地处大兴安岭成矿带北段额尔古纳地块内,是典型的斑岩型矿床。岩石Na_2O、K_2O、CaO含量变化是斑岩矿床热液蚀变的重要指示要素,蚀变(矿化)斑岩中Na_2O、K_2O的含量均低于未蚀变斑岩,而MgO、CaO、TiO_2、MnO、FeO则明显升高。通过对矿床中菊花状、鳞片状辉钼矿和斑岩侵入体中细脉状、浸染状辉钼矿Re-Os同位素测定,分别获得(202.1±9.4)Ma(MSWD=10.8)、(187.8±5)Ma(MSWD=0.17)的等时线年龄。斑岩体(脉体)侵入过程中热液活动记录与蚀变、成矿关系密切。太平川斑岩型钼铜矿床含矿斑岩体是印支末期—燕山早期碰撞造山作用背景下,新元古代增生的额尔古纳地块内花岗质地壳物质重熔形成的。The Taipingchuan Mo-Cu deposit, located in Eerguna block, northern Daxingan mountain metallogenic belt, a typi- cal porphyry deposit. The change of Na2O, K2O and CaO compositions in porphyry rocks are important indicators of hydrothermal alter- nation within porphyry deposit.The contents of Na2O and K2O in altered porphyritic rocks are lower than that in unaltered porphyritic rocks but the contents of MgO, CaO, TiO2, MnO and FeO are higher than in unaltered rocks. The hydrothermal activities are closely as- sociated with alternation and porphyritic mineralization during the process of porphyritic mass （veins）. Based on the Re-Os isotopic measurement of daisy-like, scale-like molybdenite minerals collected from the deposit area, and veinlet and disseminated molybdenite minerals collected from porphyritic intrusion, the isochron ages are as followings as （ 202.1±9.4） Ma （ MSWD = 10.8 ）, （ 187.8 ± 5 ） Ma （MSWD = 0.17）respectively. It indicted that the ore-bearing porphyritic intrusion in the Taipingchuan porphyry Mo-Cu deposit area, are formed from remelting substances of granitic rocks accreted in Neo-proterozoic Eerguna block in the tectonic setting of collisional o- rogenesis from late Indosinian period to early Yanshan period.

关 键 词：太平川钼铜矿 热液活动记录 矿化蚀变 内蒙古 

分 类 号：P618.65[天文地球—矿床学] P618.41[天文地球—地质学]