Suprasubduction zone ophiolites in the Bayanaul and Maikain–Kyzyltas zones in the northeastern part of Central Kazakhstan were studied. U–Pb dating of plagiogranites that constitute the plutonic complexes of the ophiolite sections was performed. The Early Ordovician age estimates of 480 ± 3 Ma for the plagiogranites in the Bayanaul zone and 477 ± 2 Ma in the Maikain-Kyzyltas zone were obtained for the first time. It was demonstrated that the formation time span of the plutonic and volcanosedimentary complexes in the studied ophiolites does not exceed 7–10 Ma.

中文翻译：

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哈萨克斯坦中部东北部超俯冲蛇绿岩的早奥陶世时代：斜花岗岩的 U-Th-Pb (SIMS) 测年

研究了哈萨克斯坦中部东北部 Bayanaul 和 Maikain-Kyzyltas 带的超俯冲带蛇绿岩。对构成蛇绿岩剖面深成复合体的斜长花岗岩进行了 U-Pb 测年。首次获得了 Bayanaul 带斜长花岗岩 480 ± 3 Ma 和 Maikain-Kyzyltas 带 477 ± 2 Ma 的早奥陶世年龄估计。结果表明，所研究蛇绿岩中深成岩和火山沉积复合体的形成时间跨度不超过7-10 Ma。