• 责任者：Liu Gengwu (Institute of Geology and Palaeontology ; Chinese Academy of Sciences ; Nanjing 210008 ; China) ; Chen Peiji
• 刊名：Journal of Stratigraphy
• 出版年：2013
• 卷期：37(3)
• 关键词：白垩纪 ; Cretaceous ; 古近纪 ; Paleogene ; 孢粉类型 ; palynomorphs ; 江苏 ; Jiangsu Province
• 页码：p.275-282
• 图表：illus., 34 refs.
• 分类号：1200
• issnNo：ISSN0253-4959
• isbnNo：CN32-1187/P

     The palynoflora from the Taizhou Formation of the Fengcan No. 1 drill-core in Dafeng County of northern Jiangsu contains abundant pollen. The pollen sequence can be divided into two assemblages andfive sub-assemblages. The assemblages are named following Song Z. S. ~ Qian Z. S. （1989）. The upper assemblage is called the Ulmlpollenites-Podocarpidites-Jianghanpollis assemblage （after Song Z. S. Qian Z. S. , 1989）. Its main characteristic is the rich occurrence of Ulmaceae and Pinaceae pollen. Angio- sperm pollen types dominate the assemblage, mainly are Ulmipollenites, Ulmoideipites, Subtriporopolle- nites, Plicapollis with various tricolpate, tricolporate and polyporate pollen. It also contains some rare but significant types, e. g. Paraalnipollenites, Nyssapollenites, Momipites. The most important gymno- sperm pollen are Pinuspollenites, Cedripites, and Podocarpidites. Pteridophyte spores are less than pol- len and mainly consist of Pterisosporites, Trilobosporites, Deltoidospora, Klukisporites. Based on the vertical changes of Pinuspollenites, Ulmipollenites, Podocarpidites, Trilobosporites etc. this assemblage can be separated into three subassemblages. We are inclined to assign a latest Cretaceous to Early Paleo- cene age for the upper assemblage considering the co-existence of rare Momipites, Paalnipollenites, etc. and individual Jiangsupollis, Jianghanpollis. The lower assemblage, i.e. Classopolis-Exesipollenites- Schizaeoisporites assemblage （after Song Z.S. ＆ Qian Z. S. , 1989）, is distinguished from the upper one in having more abundant Cretaceous types, such as Classopollis, Exesipollenites, Schizaeoisporites, Pterisosporites. Ulmaceae and Pinaceae pollen generally become much less important than those in the up- per assemblage. The abundant Cretaceous pollen suggests a Late Cretaceous age for the lower assemblage. Presence of rare Marsypiletes, Liliacidites complexus, Jianghanpollis and Jiangsupollis suggests that this unit presents the Wodehouseia spinita zone of Late Maastrichtian in its upper part. The lower assem- blage can be further divided into two subassemblages according to the percentage changes along stratigra- phy.  There is no fully convincing evidence to determine the Cretaceous-Paleogene boundary level in the Taizhou Formation of the Fengcan No. 1 Drill-core at the present stage. Since the sharp disappearance or great decrease of Cretaceous pollen types such as Classopollis, Exesipollenites, Schizaeoisporites, Marsypiletes, Liliacidites complexus and the appearance of rare Momipites, Paraalnipollenites etc above the boundary of the two assemblages, it is reasonable to place the Cretaceous-Paleogene boundary between the two assemblages, i.e. at the depth of 2774 m. If considering the transitional aspect of subassemblage 1-2 and a possible sediment hiatus between subassemblages 1-1 and 1-2 the boundary could also be placed at 2815 m. However, in the upper assemblage individual presence of Late Cretaceous Jiangsupollis, Jianghanpollis implies that the boundary could be moved up at a higher level. It is interesting that at a- bout 2725 m within our subassemblage 2-2 we found a pollen flora similar to the fifth subassemblage of Song Z.S. ＆ Qian Z. S. （1989）. Song Z.S.＆ Qian Z. S. （1989） placed their Cretaceous-Paleogene boundary at the bottom of their fifth subassemblage. In other words the depth of 2725 m in the Fengcan No. 1 drill-core can be correlated with the Cretaceous-Paleogene boundary of Song Z.S. ~ Qian Z. S.  （1989）. Therefore it seems also reasonable to place the boundary level at 2725 m for the Fengcan No. 1 Drill-core. However, up to date we have not seen any reported pollen assemblage that can be correlated with Song＇s subassemblage except ours from the Fengcan No. 1 Drill-core. So to place the boundary at the depth of 2747 m, the bottom of our subassemblage 2-2 will be much easier in practical work.  Sampling resolution for the present study is probably too low to find the boundary evidences for the Fengcan No. 1 Drill-core. We will raise our sampling resolution and search other support evidences in thefuture Cretaceous-Paleogene boundary study for northern Jiangsu.