摘要
The Permian Taiyuan and Shanxi formations exposed in Shandong Province,eastern North China,contain abundant spores and pollen.In this study,a total of 42 genera and 146 species of spores and pollen from these Permian formations,native to northern China,are identified and related to the three epochs of the Permian Period(Cisuralian,Guadalupian,and Lopingian Epochs)as two assemblages:Assemblage I—the Laevigatosporites-Granulatisporites assemblage,inferred as the Cisuralian(~298.9-272.9 Ma);and,Assemblage II—the Gulisporites-Sinulatisporites assemblage,inferred as the Guadalupian(~272.9-259.1 Ma).Assemblage I represents growing ferns,whereas Assemblage II represents gymnosperms.The assemblage division and analysis indicated that the palaeoclimate of the study area during Early-Middle Permian time was dominated by warm and humid conditions,and later in the Middle Permian changed into moderately dry conditions.
基金
This study was supported by the Open Foundation for the Modern Key Laboratory of Paleontology and Stratigraphy,Nanjing Institute of Geology and Paleontology,Chinese Academy of Sciences(Grant No.123104).