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阿尔金英格利萨依超高压花岗质片麻岩中锆石阴极发光图像和包裹体矿物组合特征显示, 其内部结构为由核部岩浆残留部分、幔部变质增生部分和边部后期新生部分组成的核-幔-边三层结构.对其进行的离子探针(SHRIMP)U-Pb 年龄测试结果表明, 位于锆石颗粒幔部的 5 个测点的 Pb/238U 年龄值 206为 484±11~491±12 Ma, 对应 Th/U 为 0.01~0.03, 加权平均年龄为 487±10 Ma(2σ), 应代表该岩石的变质年龄; 位于锆石颗粒核部具岩浆生长环带部位测点的 Pb/238U 年龄值介于 809±19 Ma 与 885±21 Ma 之 206间, Th/U 为 0.42~0.83, 对应于岩石的原岩岩浆结晶时代. 该岩石变质年龄(487±10 Ma)与阿尔金西段江格萨依榴辉岩峰期变质年龄(约 500 Ma)的一致性, 以及其原岩岩浆结晶年龄介于 809±19 Ma 与 885±21Ma 之间的确定, 不仅证实沿阿尔金南缘断续分布着一条超高压变质岩带, 而且进一步表明阿尔金超高压变质岩石是先存地壳物质在早古生代发生深俯冲作用的产物.
The features of zircon cathodoluminescence images and inclusion assemblages in the ultrahigh-pressure granitic gneiss show that the internal structure is composed of magmatic remnants of the core, metamorphic and hyperplastic parts of the mantle, (SHRIMP) U-Pb age test results show that the Pb / 238U age value 206 of 5 sites located in the mantle of zircons is 484 ± 11 ~ 491 ± 12 Ma, the corresponding Th / U is 0.01 ~ 0.03, and the weighted average age is 487 ± 10 Ma (2σ), which should represent the metamorphic age of the rock. The Pb / 238U ages of the Pb ranged from 206 Ma to 808 Ma and 885 Ma to 21 Ma with a Th / U of 0.42 to 0.83, which corresponded to the protolith magmatic age of the rocks with a metamorphic age of (487 ± 10 Ma) It is consistent with the metamorphic age (about 500 Ma) of the Aegis eclogite eclogites in the Arjin west segment and the determination of the age at which the protolith magma was crystallized between 809 ± 19 Ma and 885 ± 21 Ma, Altun southern edge of the intermittent distribution of a UHP metamorphic belt, Furthermore, it is further demonstrated that the Altyn-Eden metamorphic rocks are the result of deep subduction of pre-existing crustal materials in the Early Paleozoic.