1. The authors practiced pollen analysis with the core samples on the Narita formations and assumed the paleoclimate in the process of the deposition of the formations at Akashi area, Tsukuba-machi, and Kamigo area, Toyosato-machi, Tsukubagun, Ibaragi Prefecture. 2. The core samples at the two stations were collected by percussion boring and their stratigraphy were divided as follows: Akashi I (0-13 m), II (13-39 m), III (39-100 m) Kamigo I (5-15 m), II (15-56 m), III (56-146 m) 3. The core samples on which we practiced pollen analysis were collected every one meter from the following depth: Akashi; 11 m, 18 m, 66-70 m, 90-96 m. Kamigo ; 8 m, 9 m, 24 m, 66-69 m, 80-88 m, 120 m, 121m. 4. Though each horizon has the appearance rate of fossil pollen different from each other, the fossil pollen grains of Pinus, Abies, Picea, Tsuga, Fagus, Quercus, Alnus, Ulmaceae and others were generally recognized. And these pollen grains were investigated in detail on the basis of the frequency of the size of each grain. 5. It may be assumed that the paleoclimate in the process of the deposition of Narita formations was warm without great difference from present one, except that cool climate was recognized in the upper horizon of II of Akashi and the lower horizon of III of Kamigo.
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