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江苏北部丰参一井泰州组孢粉植物群可以分为上下两个组合,暂时借用宋之琛等(1981)提出的组合名称来命名当前的组合:上部组合命名为Ulmipollenites-Podocarpidites-Jianghanpollis组合,以榆科和松科花粉高含量为特征;下部组合命名为Classopolis-Exesipollenites-Schizaeoisporites组合,含丰富的克拉梭粉属(Classopollis)、隐孔粉属(Exesipollenites)、希指蕨孢属(Schizaeoisporites)、凤尾蕨孢属(Pterisosporites)等常见于白垩纪的孢粉类型。考虑到下部组合的上部时代属于晚白垩世晚期,而上部组合既有少许Paraalnipollenite,Momipites等出现,也有个别江苏粉、江汉粉等存在,时代上难以排除晚白垩世晚期的可能。在丰参一井的白垩系-古近系界线具体位置也难以确定,虽然我们倾向将界线置于2774m,但根据目前资料,井深2815m,2747m,或者甚至2716m上下都有可能。在丰参一井既没有发现可以和北美西部相应层位直接对比的白垩系-古近系界线附近的孢粉组合,也没有见到所谓的孢子高含量组合的层位,因此也不能肯定是否存在白垩系-古近系界线沉积。由于丰参一井的采样密度比较低,也不能轻易排除因为采样密度不够而遗漏了界线沉积的可能性。江苏北部不属于真正的鹰粉区,不宜和我国东北以及北美西部进行直接对比,其界线附近的孢粉植物群面貌和演变情况还需要进一步探索。
The sporopollen assemblages in the Fengshen-Jingzhou Taizhou Formation in northern Jiangsu can be divided into upper and lower combinations, and the current combination is tentatively borrowed by the combination name proposed by Song et al. (1981): the upper combination is named Ulmipollenites-Podocarpidites-Jianghanpollis combination, Branch and Pinaceae pollen is characterized by high content; the lower part of the combination named Classopolis-Exesipollenites-Schizaeoisporites combination, rich class of Pollack class (Classopollis), Exposeipollenites, (Schizaeoisporites) Pterisosporites (Pterisosporites) and other commonly found in the Cretaceous type of sporopollen. Considering that the upper age of the lower assemblage belonged to the late Late Cretaceous, the upper assemblage not only appeared a few Paraalnipollenite and Momipites, but also existed in some Jiangsu and Jianghan flouries. It is difficult to rule out the late Cretaceous in the age. The exact location of the Cretaceous-Paleogene boundary at Fengshen-Ii is difficult to determine. Although we tend to place the boundary at 2774 m, according to the current data, the well depth is 2815 m, 2747 m, or even 2716 m up and down. Neither the sporopollen assemblages near the Cretaceous-Paleogene boundary that can be directly compared with the corresponding horizon in western North America have been found in the Fengshen-1 well nor the so-called high-spore assemblages, nor can we be certain whether There is Cretaceous - Paleogene boundary deposition. Due to the relatively low sampling density of Feng-sen one well, it is not easy to exclude the possibility of missing the boundary sedimentation due to insufficient sampling density. The northern part of Jiangsu Province does not belong to the real Yingli area and should not be directly compared with the northeast of China and the western part of North America. The appearance and evolution of the pollen flora near the boundary line need to be further explored.