Ages of the Laocheng Granitoids and Crustal Growth in the South Qinling Tectonic Domain, Central China: Zircon U-Pb and Lu-Hf Isotopic Constraints
  • 【摘要】

    The Laocheng granitoid pluton is located in the South Qinling tectonic domain of the Qinling orogenic belt,southern Shaanxi Province,and consists chiefly of quartz diorite,granodiorite and monzogranit... 展开>>The Laocheng granitoid pluton is located in the South Qinling tectonic domain of the Qinling orogenic belt,southern Shaanxi Province,and consists chiefly of quartz diorite,granodiorite and monzogranite.A LA-ICP-MS zircon U-Pb isotopic dating,in conjunction with cathodoluminescence images,reveals that the quartz diorite and granodiorite were emplaced from 220 Ma to 216 Ma,while the monzogranite was emplaced at ~210 Ma.In-situ zircon Hf isotopic analyses show that the εHf(t) values of the quartz diorite and granodiorite range from -8.1 to +1.3,and single-stage Hf model ages from 809 Ma to 1171 Ma,while the εra(t) values of the monzogranite are -14.5 to +16.7 and single-stage I-If model ages from 189 Ma to 1424 Ma.These Hf isotopic features reveal that the quartz diorite,granodiorite and monzogranite were formed from the mixing of the magmas derived from partial melting of the depleted mantle and the lower continent crustal materials,and there were two stages of continental crust growth during the Neoproterozoic (~800 Ma) and Indosinian (~210 Ma) eras,respectively,in the south Qiniing tectonic domain of the Qiniing orogrnic belt,Central China. 收起<<

  • 【作者】

  • 【作者单位】

    The Key Laboratory of Orogenic Belts and Crustal Evolution/Institute of Mineral Resources/Northwest Geological Exploration and Mining Bureau for Nonferrous Metals/Institute of Geology

  • 【刊期】

    地质学报(英文版) SCI 2011年4期

  • 【关键词】

    Laocheng granitoid pluton  LA-MC-ICP-MS  zircon U-Pb dating  zircon Hf isotopes  petrogenesis  south Qinling tectonic domain 

  • 【基金项目】

    This study is financially supported by the National Project of Scientific and Technological Support