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最近的研究成果表明,在大兴安岭新林-喜桂图旗断裂东段的吉峰、嘎仙、环二库地区存在一些蛇绿岩岩石组合.在大兴安岭地区大扬气林场环二库蛇绿混杂岩中的花岗岩中获得锆石LA-ICP-MS U-Pb年龄为557.2±2.2 Ma,表明其形成于新元古代晚期.岩石总体上具略贫碱,弱过铝质钙碱性,具有不明显的Eu负异常,为弱过铝钙碱性Ⅰ型花岗岩.岩石富集轻稀土元素和Hf、Ba、Nd、U等元素,相对亏损Th、Nb、Ta、Zr等元素.结合新元古代末期新林-吉峰地区存在新元古代洋盆,认为该岩体可能形成于该大洋俯冲环境.
Recent research results show that there are some ophiolitic rock assemblages in the Jifeng, Gaxian and Huancui areas in the eastern part of the Xinlin-Xiguangtuqi fault in the Greater Xing’an Mountains. In the Great Yang’an Mountains area, The zircon LA-ICP-MS U-Pb dating of granite was 557.2 ± 2.2 Ma, indicating that it was formed in the late Neoproterozoic. The rock generally has a slightly-poor base and a weakly perovskite with an insignificant Eu negative anomaly, which is a weak Al-Ca-Ca type alkaline granite.The rocks are enriched in LREE, Hf, Ba, Nd, U and other elements and relatively depleted in elements such as Th, Nb, Ta and Zr.Combined with the late Neoproterozoic The Neo-Lin-Yifeng area is characterized by the Neoproterozoic ocean basin, which is thought to be formed in the oceanic subduction environment.