北辽河群浪子山组地层的重新厘定

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古元古代北辽河群浪子山组变质沉积岩系主要分布在辽宁省鞍山市、海城市、辽阳市一带，其岩石组合以石英岩、片岩、千枚岩、变粒岩夹大理岩、透闪岩等为主，原岩恢复为砂岩、泥质砂岩、泥岩、泥灰岩等。前人将其置于北辽河群底部。通过对南北辽河群各组进行了详细的地质调查和分析对比工作，依据岩石组合特征和锆石年代学数据，笔者认为浪子山组应与南辽河群盖县组层位相当，故浪子山组不宜置于辽河群底部而应重新厘定为北辽河群顶部。The Paleoproterzoic clastic rocks are widely distributed in the southern portion of Liaoning prov-ince, grouped as the Langzishan Formation of the North Liaohe Group. The Langzishan Formation, previously defined as the bottom of the North Liaohe Group, mainly consists of sandstone, shaly sandstone, clay rock, siltstone interbedded with limestone, and argillaceous limestone. They were metamorphosed to be quartzite, schist, phyllite, marble, and tremolite rocks. Based on detailed field investigation, integrating with zircon U-Pb data, we proposed that the Langzishan Formation is equivalent to the Gaixian Formation (top of the South Liaohe Group). The Langzishan Formation should be grouped into the upper clastic sequence of the North Liaohe Group, but not the bottom as previous consideration.