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皖南地区井潭组变质火山岩原划归新元古界历口群，层位在中元古界上溪群之上。通过重新认识本区的地质条件后，发现它是一套生成于岛弧环境的钙碱性火山岩组合，而原上溪群中部分地层则是与之有关的火山沉积，其层位应在井潭组变质火山岩之上。本次对井潭组变质火山岩ＳｍＮｄ同位素年龄的研究获得以下信息：一是井潭组的等时线年龄为９９０Ｍａ，指示其形成时代为新元古代；二是其模式年龄平均为１８０７Ｍａ，结合上溪群中已有的ＳｍＮｄ模式年龄和其他地质资料，进一步证明它是原上溪群的物源供给区；三是以井潭组变质火山岩为主体的构造岩石单位可以与浙江的双溪坞群和江西的双桥山群部分层位对比。这些信息为认识本区乃至整个“江南古陆”的构造格局和演化提供了重要的佐证。
The metamorphic volcanic rocks of the Jingtan Formation in southern Anhui are assigned to the Liguogroup of Neoproterozoic and the layers are above the Shangxi Group in the Middle Proterozoic. After re-understanding of the geological conditions in this area, it is found that it is a set of calc-alkaline volcanic assemblages formed in the island arc environment, and part of the original Shangxi Group is associated with volcanic sediments, the layers should be in the well Tam Group metamorphic volcanic rocks above. The current research on SmNd isotopic age of metamorphic volcanic rocks in the Jingtan Formation has the following information: First, the isochron age of the Jingtan Formation is 990Ma, indicating that the formation age was Neoproterozoic; second, the average age of its model is 1807Ma, Combined with the existing age of SmNd model in Shangxi Group and other geological data, it is further proved that it is the source of the original Shangxi Group. Thirdly, the tectonic units based on metamorphic volcanic rocks of Jingtan Formation can be combined with those of Zhejiang Shuangxiu dock group and Shuangqiao group in Jiangxi Province. These information provide important evidences for understanding the tectonic framework and evolution of this area and even the entire “Jiangnan ancient land.”