杨兴科, 何虎军, 晁会霞, 朱昊磊, 韩珂, 王北颖. 2023: 岩浆核杂岩和变质核杂岩特征对比及控矿实例——南秦岭牛山-凤凰山变质核杂岩和牛山北岩浆核杂岩构造群落及控矿模式. 地质通报, 42(4): 520-539. DOI: 10.12097/j.issn.1671-2552.2023.04.003
    引用本文: 杨兴科, 何虎军, 晁会霞, 朱昊磊, 韩珂, 王北颖. 2023: 岩浆核杂岩和变质核杂岩特征对比及控矿实例——南秦岭牛山-凤凰山变质核杂岩和牛山北岩浆核杂岩构造群落及控矿模式. 地质通报, 42(4): 520-539. DOI: 10.12097/j.issn.1671-2552.2023.04.003
    YANG Xingke, HE Hujun, CHAO Huixia, ZHU Haolei, HAN Ke, WANG Beiying. 2023: Comparison of characteristics between magmatic core complex and metamorphic core complex and examples of ore control: Tectonic community and ore controlling model of Niushan-Fenghuangshan metamorphic core complex and North Niushan magmatic core complex in the South Qinling Mountains. Geological Bulletin of China, 42(4): 520-539. DOI: 10.12097/j.issn.1671-2552.2023.04.003
    Citation: YANG Xingke, HE Hujun, CHAO Huixia, ZHU Haolei, HAN Ke, WANG Beiying. 2023: Comparison of characteristics between magmatic core complex and metamorphic core complex and examples of ore control: Tectonic community and ore controlling model of Niushan-Fenghuangshan metamorphic core complex and North Niushan magmatic core complex in the South Qinling Mountains. Geological Bulletin of China, 42(4): 520-539. DOI: 10.12097/j.issn.1671-2552.2023.04.003

    岩浆核杂岩和变质核杂岩特征对比及控矿实例——南秦岭牛山-凤凰山变质核杂岩和牛山北岩浆核杂岩构造群落及控矿模式

    Comparison of characteristics between magmatic core complex and metamorphic core complex and examples of ore control: Tectonic community and ore controlling model of Niushan-Fenghuangshan metamorphic core complex and North Niushan magmatic core complex in the South Qinling Mountains

    • 摘要: 以南秦岭牛山-凤凰山变质核杂岩和牛山北岩浆核杂岩为例, 通过核杂岩的构造群落、变质程度、岩浆侵位与变形时代、构造层次与演化、控矿特征与控矿构造-蚀变岩相填图及测年研究, 对比2类核杂岩的特征及其控矿作用。结果表明, 2类核杂岩有相似的结构样式, 但构造群落和演化差别较大。牛山-凤凰山变质核杂岩核部为新元古代武当岩群和耀岭河岩组中深变质岩, 其中可见新元古代石英闪长岩和加里东期辉石岩-辉绿岩株, 说明是在新元古代或加里东期形成的。核杂岩与外围震旦系—泥盆系浅变质岩间由剥离断层及韧性剪切带分割。志留系梅子垭岩组为浅变质强变形的岩片组合, 发育多层次韧性剪切、固态流变、滑脱-逆冲-走滑变形3期新生面理及其置换。而牛山北岩浆核杂岩核部和外围是浅变质岩, 在核部和外围填图、测试时发现新元古代、早古生代、三叠纪、侏罗纪4期侵入岩, 与岩浆核杂岩相关的有三叠纪—早侏罗世二长花岗岩株和晚侏罗世花岗岩脉2期侵入岩。研究发现, 与岩浆核杂岩伴随的岩浆侵位、韧性剪切变形与热变质增温-变斑晶加大-自然金沿S2面理分布-金矿化热液蚀变等的时代均集中在晚三叠世—侏罗纪, 指示了时代较新的陆内造山期岩浆核杂岩的脆-韧性剪切变形-立交桥式岩浆-热力垂向增生-热液蚀变成矿时空关联特点及深部找矿方向。

       

      Abstract: Taking the metamorphic core complex of Niushan-Fenghuangshan(NFMtCC)in the southern Qinling Mountains and the North Niushan magmatic core complex (NMgCC) as examples, this study compares the characteristics and ore-controlling effects of the two types of core complexes. The research method is to compare and analyze the structural community, metamorphic degree, magma emplacement and deformation era, structural hierarchy and evolution, and ore control characteristics of the nuclear complex, combined with ore control structure alteration lithofacies mapping and dating research. The results indicate that the two types of core complexes have similar structural styles, but there are significant differences in their tectonic communities and evolution. The core of Niushan-Fenghuangshan metamorphic core complex is the Neoproterozoic Wudang rock group and Yaolinghe rock group medium deep metamorphic rock, with Neoproterozoic quartz diorite and Caledonian pyroxene diabase strain, indicating that it was formed in Neoproterozoic or Caledonian. There are detachment faults and ductile shear zones between the core complex and the surrounding Sinian Devonian shallow metamorphic rock. The Meiziya Formation of the Silurian system is a combination of shallow metamorphic and strongly deformed rock slices, with three stages of newly formed foliation and replacement, including multi-level ductile shear, solid-state rheology, detachment thrust strike slip deformation. The core and periphery of the North Niushan magmatic core complex are shallow metamorphic rock, and four intrusive rocks of Neoproterozoic, early Paleozoic, Triassic and Jurassic are found in the core and periphery by mapping and testing. There are two phases of intrusive rock related to the magmatic core complex: Triassic-Early Jurassic monzonitic granite stock (180.2±3.6 Ma, 176.0±1.9 Ma) and Late Jurassic granite vein (156.5 Ma). This research has found that the magma emplacement, ductile shear deformation, and thermal metamorphism accompanied by the magma core complex, as well as the increase of metamorphic phenocrysts, the distribution of natural gold along the S2 plane, and the hydrothermal alteration of gold mineralization, are all concentrated in the Late Triassic-Jurassic, indicating the spatiotemporal correlation characteristics of the brittle ductile shear deformation, overpass type magma, thermal vertical accretion, and hydrothermal alteration of the magma core complex during the relatively new era of intracontinental orogeny, as well as the direction of deep exploration.

       

    /

    返回文章
    返回