Shenshangou section is located in the northeastern Ordos Basin,Dongsheng area of Inner Mongolia. Jurassic Yan'an Formation and Zhiluo Formation contain abundant sporopollen fossils.The Yan'an Formation is a coal-bearing strata,and is composed of grayish white sandstone,grey siltstone with mudstone,few conglomerate layer,and 5-6sets of coal seam.The Zhiluo Formation is an important uranium bearing rock series.It consists of gray greenish sandstone,grey siltstone with purple red mudstone and mud silty rocks.On the basis of the profile of ShenshangouYan'an Formation and Zhiluo Formation sporopollen analysis,we identifiedtwo assemblage zone of Cyathidites-Dictyophyllidites-Cycadopites(CDC)and Cyathidites-Osmundacidites- Lycopodiumsporites-Concentrisporites-Disacciatrileti (COLCD)in the Yan'an Formation,which indicate that the age of Yan'an Formation was the Early to Middle Jurassic.Sporopollen assemblage zone of the Zhiluo Formation is composed of Cyathidites-Osmundacidites-Cycadopites-Disacciatrileti (COCD)with the Middle Jurassic era.Comprehensive geology,element geochemistry,and the quantitative analysis of fossil plants and sporo-pollen fossils showed that from the Yan'an Formation to the Zhiluo Formation deposition period the climate changed from the subtropical warm and humid to arid and semi-arid hot,reflecting an important ancient climate change event in the early Yan'an movement during the Early Jurassic,which may have special geological significance for the coal and sandstone type of uranium mineralization.