内蒙古巴林右旗下三叠统幸福之路组化石新发现

New discovery of fossils in the Lower Triassic Xingfuzhilu For- mation,Bairin Right Banner,Inner Mongolia

下三叠统幸福之路组分布于大兴安岭南部,时代为早三叠世。重新实测了幸福之路组三段建组剖面,采集了孢粉、叶肢介、双壳及植物化石,其中孢粉化石为首次发现。孢粉化石为Alisporites communis-Vittatina costabilis组合,叶肢介为Cyclotunguzites-Euestheria组合。综合分析孢粉、叶肢介化石组合特征,认为其时代相当于早三叠世早期;幸福之路组孢粉组合在古植物地理区划上与新疆北部晚二叠世—早三叠世孢粉组合关系密切,但也含有华北地台晚二叠世晚期的一些分子,记录了安加拉和华夏两大植物群的交流。幸福之路组与林西组孢粉组合具有明显的连续性。

The Early Triassic Xingfuzhihi Formation is distributed in the southern part of the Da Hinggan Mountains. The stratotype of the 3rd Member of the formation was reinvestigated by the authors. Magaplant fossils, pollen and spores, conchostracans and bi- volves were found along the stratotype section. Among them, the pollen and spores were discovered for the first time. They are named the Cyclotunguzites-Euestheria assemblage and the A lisporites communis-Vittatina eostabilis assemblage respectively. The age of the stratotype section is early Early Triassic according to the newly-discovered conchostracans and pollen and spores. The florisfic province of the pollen and spores on the section is closely related to the Permian-Triassic pollen and spores assemblages widely distributed in the Junggar basin, but slightly different from the latter in possessing some Late Lopingian elements of North China Platform.