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利用相似系数(CS)公式, 进行了定量的古地理分区研究. 结果表明, 中寒武世晚期至晚寒武世中期的副牙形石和原牙形石存在地理分区. 奥陶纪牙形石的地理分区可以追溯到中寒武世晚期. 中寒武世晚期可划分出华北和华南分区, 晚寒武世早期和中期均可划分出华北、华南和波罗的分区. 探讨了大的分区, 即动物群分区在上述时期已存在的可能性, 提出了北美中部大陆动物群分区和大西洋动物群分区在晚寒武世早期业已存在的推断. 华北分区属于北美中部大陆动物群分区内的次一级分区, 波罗的分区属于大西洋动物群分区内的次一级分区, 而华南分区是介于两大动物群分区之间的次一级分区. 此外, 还与研究基础雄厚的三叶虫地理分区进行了对比, 并修正了华北、华南和塔里木地块的古地理位置.
Using the similarity coefficient (CS) formula, a quantitative palaeogeographic study was conducted and the results show that there are geographical sub-types of palaeotates and protoliths from the middle of the Middle Cambrian to the middle of the Late Cambrian. The Ordovician conodont geography The division can be traced back to the middle of the Middle Cambrian, and can be divided into the North China and South China sub-regions in the middle Cambrian, and the sub-regions of North China, South China and Baluo in the early and middle Late Cambrian. The possibility that zoological subdivisions existed during the above period suggested the presumed existence of the fauna of the fauna of the central continent of North America and the fauna of the Atlantic during the early Late Cambrian. The North China subfamily belongs to the subordinate class of fauna in the central North American continent Partition, Baltic Division belongs to the sub-region of the Atlantic fauna sub-level sub-area, and South China sub-area is between the two major fauna sub-area sub-level sub-area. In addition, Compared the paleogeographic positions of the North China, South China and Tarim plots.