内蒙古阿鲁科尔沁旗陶海营子剖面 林西组化石新发现

大兴安岭地区上二叠统林西组一直笼统地被划归为上二叠统,目前仍旧缺少更进一步的划分对比意见.阿鲁科尔沁旗陶海营子剖面是林西组的典型剖面之一.剖面实测过程中,在多个层位均发现有孢粉、植物、叶肢介、双壳化石,其中孢粉化石为首次发现.孢粉化石为Kraeuselisporites spinulosus-Alisporites communis组合,叶肢介化石为Palae olimnadia-C yc lotunguzites组合.综合研究孢粉、叶肢介等门类化石的组合特征,认为该剖面林西组可与新疆吉木萨尔大龙口剖面的梧桐沟组—锅底坑组中下部进行对比,时代为晚二叠世晚期.

New fossil discovery along the section of Linxi Formation at Taohaiyingzi in Ar Horqin Banner, Inner Mongolia

The section of Linxi Formation at Taohaiyingzi in Ar Horqin Banner of Inner Mongolia is one of typical sections in northeastern China. Abundant fossils such as sporopollen, conchostracan, bivalves and megaplants were found along the section. Among them, sporopollen were discovered for the first time and named Kraeuselisporites spinulosus- Alisporites communis assemblage. Meanwhile, the conchostracans are named Palaeolimnadia-Cyclotunguzites assemblage. The fossil assemblages of Linxi Formation along the section can be correlated with those in Wutonggou Formation and the lower and middle part of Guodikeng Formation along the Dalongkou section in Jimsar, Xinjiang. Therefore, the Linxi Formation at Taohaiyingzi is late Late Permian in age, and can be correlated only to the upper part of the Linxi Formation in the type section in Guandi Town, Linxi County of Inner Mongolia, northeastern China.