Abstract:

Based on the analysis of the samples from drill hole 5005,we discovred an sporo-pollen assemblege of Aratrisporites,Alisporites and Colpectopollis.Similar assemblege of fern and pollen can be found in corresponding group,such as Huangshanjie Group in Junggar Basin,Tuha Basin and Shantanghu Basin,Yanchang Group in Ordos Basin,Yangcaogou Group in Liaoxi.These members could often be found in Triassic System.It is suggested that the formation should belong to Upper Triassic.