内蒙古狼山地区宝音图地块是兴蒙造山带微地块之一.采用SHRIMP和LA ICP-MS锆石U-Pb测年技术,对宝音图地块中变质侵入体和宝音图群石英岩中的锆石进行了同位素年代学研究,获得了变质侵入体SHRIMP锆石U-Pb年龄1672±10Ma和宝音图群石英岩的碎屑锆石U-Pb下限年龄1426Ma,限定了宝音图群的形成时代应晚于1426Ma.同时根据宝音图群碎屑锆石年龄谱构造-热事件信息与华北克拉通构造-热事件年龄谱对比的相似性,揭示了宝音图群的碎屑来源于华北克拉通,认为宝音图地块与华北克拉通更具亲缘性,可能为华北克拉通的一部分.%The Baoyintu block of the Langshan area in Inner Mongolia is one of the oldest microcontinents in the the Xingmeng orogenic belt. Analysis of SHRIMP and LA-MC-ICP-MS zircon U-Pb ages was conducted for zircons from the metamorphic intrusive body and Baoyingtu Group. The results show a zircon U-Pb age of of 1672+10 Ma for the Baoyintu metamorphic intrusive body has and a low detrital zircon age of 1426 Ma is for the Baoyintu Group, which constrains the formation age of the Baoyingtu Group later than 1426 Ma. The comparison on the tectonic-thermal events of both the Baoyingtu Group detrital zircons and the North China Craton reveals that the Baoyintu Group is Mesoproteozoic in age and originated from the North China Craton, indicating that the Baoyintu Group is likely closely related with the North China Craton and is likely part of the North China Craton.
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