The Early Paleozoic age of the protolith for gneisses in the East Uralian megazone (South Urals) is proved by zircon dating. Two metamorphic complexes have been identified in the eastern framing of the Middle–Late Paleozoic Suunduk granitoid pluton. The Zelenodolsk complex is represented by granitic gneisses, while the Kusakan complex (Kusakan Formation) is represented by metavolcanic gneisses, crystalline schists, and quartzites. U–Th–Pb analyses (SHRIMP II) of accessory magmatic zircons from the Zelenodolsk granitic gneiss yielded dates of 478 ± 5 Ma. The protolith age of the Kusakan gneiss (andesitic metatuff) is 529 ± 6 Ma. The origin of volcanic, volcanosedimentary rocks, and granitoids in the East Uralian megazone is associated with the evolution of the volcanoplutonic belt in the active continental margin.

中文翻译：

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南乌拉尔东部片麻岩和花岗片麻岩的早古生代原生岩：U-Th-Pb (SIMS) 年代学研究结果

锆石测年证实了东乌拉尔大带（南乌拉尔）片麻岩原岩的早古生代时代。在中-晚古生代 Suunduk 花岗岩体的东部框架中已经确定了两个变质杂岩体。Zelenodolsk 杂岩以花岗片麻岩为代表，而 Kusakan 杂岩（Kusakan 组）以变火山片麻岩、结晶片岩和石英岩为代表。来自泽列诺多尔斯克花岗片麻岩的副岩浆锆石的 U-Th-Pb 分析 (SHRIMP II) 得出的日期为 478 ± 5 Ma。草寒片麻岩（安山质变质岩）的原岩年龄为 529 ± 6 Ma。东乌拉尔大带火山、火山沉积岩和花岗岩的成因与活动大陆边缘火山深成岩带的演化有关。