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东昆仑造山带晚古生代—早中生代由于布青山-阿尼玛卿洋的俯冲发育有大量岛弧型花岗岩类。选取东昆北巴隆地区朝火鹿陶勒盖花岗闪长岩体寄主岩和闪长质暗色微粒包体进行了岩相学、LA-ICP-MS锆石U-Pb年代学及地球化学研究。结果表明,岩体寄主岩的结晶年龄为242.3±1.3Ma,暗色微粒包体结晶年龄为241.2±0.8Ma,显示其形成于中三叠世;寄主岩和暗色微粒包体A/CNK值介于0.86~1.06之间,为准铝质-弱过铝质;稀土元素总量分别为119×10~(-6)~170×10~(-6)、189×10~(-6),稀土元素配分模式显示右倾型,具有负Eu异常;岩石富集Rb、Ba、Th等大离子亲石元素,亏损Nb、Ta、Ti等高场强元素,具有弧岩浆岩特征。野外及岩相学特征均显示包体为基性岩浆进入酸性岩浆快速冷凝形成的,为俯冲板片断离导致幔源岩浆上侵形成的岩浆混合作用的产物,是布青山-阿尼玛卿洋俯冲晚期的岩浆记录。
Late Paleozoic in the East Kunlun orogenic belt - Early Mesozoic There are a large number of island arc-type granite classes due to the subduction of the Buqunshan-Animaqing ocean. The lithology, LA-ICP-MS zircon U-Pb geochronology and geochemistry of the host rock and the dioritic microparticles inclusions in the Hulu Luoluoleiguan granodiorite body were selected from the Barong area, East Kunlun area. the study. The results show that the crystallization age of host rocks is 242.3 ± 1.3Ma and the dark-colored inclusions are 241.2 ± 0.8Ma, indicating that they are formed in Middle Triassic. The A / CNK values of host rocks and dark-colored particles are between 0.86 ~ 1.06, which are quasi-aluminum-weak permanganate. The contents of rare earth elements are 119 × 10 -6 -6 170 × 10 -6, 189 × 10 -6, The elemental distribution patterns show a right-tilting pattern with a negative Eu anomaly. The rocks are enriched in large ion lithophile elements such as Rb, Ba and Th, depleted in high-field elements such as Nb, Ta and Ti and characterized by arc magmatic rocks. The field and petrographic features show that the inclusions are formed by the rapid condensation of basic magma into acidic magma and are the product of magmatic mixing caused by mantle-derived magmatic intrusion on the subducting slab. These are the products of the Buqingshan-Animaqing ocean Subduction of Late Magma Records.