夏日哈木矿区早泥盆世镁铁质岩墙群的年代学特征及地质意义  

Zircon U-Pb geochronology and geological significance of Early Devonian mafic dyke swarms in Xiarihamu ore district

作　　者：王冠 孙丰月[2] 李碧乐[2] 李世金 奥琮 Wang Guan;Sun Fengyue;Li Bile;Li Shijin;Ao Cong(School of Mining Engineering,Heilongjiang University of Science & Technology,Harbin 150022,China;College of Earth Sciences,Jilin University,Changchun 130061,China;Qinghai Geological Survey,Xining 810008,China;Tianjin Institute of Geology & Mineral Resources,Tianjin 300170,China)

机构地区：[1]黑龙江科技大学矿业工程学院,哈尔滨150022 [2]吉林大学地球科学学院,长春130061 [3]青海省地质调查局,西宁810008 [4]天津地质矿产研究所,天津300170

出　　处：《黑龙江科技大学学报》2019年第1期35-40,共6页Journal of Heilongjiang University of Science And Technology

基　　金：黑龙江省省属本科高校基本科研业务费项目(Hkdcx201805)

摘　　要：为厘定夏日哈木矿区幔源岩浆活动的时限和成岩构造环境,对该矿区镁铁质岩墙群开展岩相学和锆石U-Pb年代学研究。结果表明,该套镁铁质岩墙群以细粒辉长岩为主,结晶侵位年龄为415. 7±1. 6 Ma,平均标准权重偏差为0. 16,属早泥盆世,形成于造山后伸展的构造环境,其形成可能与碰撞拼贴后俯冲板片的断离作用有关。晚志留世—早泥盆世时期,东昆仑地区发生了强烈的幔源岩浆活动,为岩浆铜镍硫化物矿床的形成提供了优越的成矿地质条件。This paper introduces a new petrographical and zircon U-Pb chronologic study on the mafic dyke swarms in Xiarihamu ore district in an attempt to constrain the formation time of mantle derived magma and the tectonic setting for the mafic dyke swarms.The research concludes that mafic dyke swarms consisting dominantly of fine-grained gabbros,with the crystallization and emplacement age of 415.7+1.6 Ma(MSWD 0.16)are classified as Early Devonian,indicating that the swarms were formed in post-orogenic extensional tectonic environment--the formation possibly associated with the break-off of the subduction slab following collision and collage;and the occurrence of strong mantle-derived magmatism in the eastern Kunlun area during the Late Silurian-Early Devonian has provided favorable metallogenic geological conditions for the formation of magmatic copper-nickel sulfide deposits.

关 键 词：镁铁质岩墙 锆石 U-PB年代学 构造环境 

分 类 号：P597.3[天文地球—地球化学]