山形県炭田の花粉分析学的研究 第2報 : 特に西田川炭田の花粉分析

抄録

1. Pollen analysis was carried out on Meiocene lignite samples obtained from the Nishitagawa coal field, Yamagata Prefecture. 2. Examining the pollen of Alnus and 36 other kinds of tree, a comparative study was made on the pollen flora in each bed. 3. Such pollen grains of extinct plants as Sequoia, Taxodium, Cunninghamia, Liquidambar, and others were found most predominantly in the Aburato coal bearing bed. 4. As the pollen flora of the plants of the temperat and sub-tropical zones is found abundan, it may be said that the environment of that age was similar. 5. The pollen speicies observed in this analysis are similar to those of the Mogaml and Okitama coal fields, both of which belong to Pliocene. Therefore, it is concluded at least that the same kinds of tree as the present have survived since the beginning of Neogene-Tertiary.