• 责任者：Ji Liming (Key Laboratory of Petroleum Resources Research ; Institute of Geology and Geophysics ; Chinese Academy of Sciences ; Lanzhou 730000 ; China) ; Zhu Youhua
• 刊名：Acta Palaeontologica Sinica
• 出版年：2013
• 卷期：30(4)
• 关键词：延长组 ; Yanchang Formation ; 孢粉组合 ; palynological assemblage ; 古气候 ; paleoclimate ; 鄂尔多斯盆地 ; Ordos Basin
• 页码：p.367-378
• 图表：6 illus., 1 table, 21 refs.
• 分类号：1200
• issnNo：ISSN0001-6616
• isbnNo：CN32-1188/Q

     Abundant sporo-pollen fossils were found in cores from the Chang 8 and Chang 7 members of the Yanchang Formation in the southwestern Ordos basin, NW China. The assemblage of Chang 8 member was denominated by Aratisporiteas-Punctatisporites, and the assemblage of Chang 7 member as Asseretospora-Walchiites. Their charae teristies are similar to those of the assemblages of the Tongchuan Formation and the Yanebang Formation in the southeast Ordos basin, respectively. Their geological ages are Ladinian of late Middle Triassic and Carnian of early Late Triassic respectively. The sporo-pollen and their ecological distributions in these members suggest the paleocli mate of the eastern Gansu Province in the Middle and Late Triassic was warm and wet, under a temperate to subtropi cal zone. The wetter paleoenvironment during the Chang 8 and Chang 7 sections deposited in eastern Gansu Province large-scale lake transgression was happening, with the largest lake.