The writers attempted to clarify the late Quaternary stratigraphy and climatic change through the subsurface sections in the central part of Fukuoka City on the basis of pollen analysis. Four pollen zones were recognized, which respectively correspond to FG, RI, RII and RIIIb zones of NAKAMURA, J. (1952, 1967, 1975a, 1975b) and TSUKADA, M. (1963, 1967, 1974) in ascending order. In view of paleoclimate, these pollen zones represent respectively a climatic period.
1. Cold period (FG zone): the peat layer (910-950cm) is mainly characterized by north temperate elements, such as Abies, Tsuga, Betula, Carpinus, Fagus, Ulmus, Tilia, Alnus, etc. and wholly excludes south temperate elements such as Celtis, Shiia, Cyclobalanopsis, Gleichenia, Pteris, etc. North temperate forest probably expanded to the low land with its lower boundary about 1000-1500m lower than that in the present day.
2. Cold period (RI zone): the beds (838-895cm) consisting of irregular bodies of sands, silts and gravels hold very poor pollen records. The result is not effective to correlate this section decidedly with RI or LG zone (L zone) and so we tentatively correlate it to RI zone on the basis of the geological field data. In general RI is regarded as a transition zone between the cold period LG (L) and the next warm period RII.
3. Warm period (RII zone): it is generally accepted that the colder forest of the former period was pushed away by such south temperate elements as Shiia and Cyclobalanopsis which became dominant. However there are small quantities of north temperate elements throughout these layers (680-838cm). While Celtis decreases at the upper part of these layers, Cyclobalanopsis and Shiia increase.
4. Decreasing warm period (RIIIb zone): the peaty mud layer (365-400cm) is characterized by a large quantity of Pinus, while evergreen broad leaved species are not many. Cereal pollen were also recognized in the samples from. this section. The above facts suggest destruction of forest and agricultural activities by man as NAKAMURA, J. (1971, 1975b) and TSUKADA, M. (1974) pointed out.
¹⁴C age of molluscan shells from about 4m level under the ground surface was 5540±100y.B.P. (KURI 185, T. SAKATA) and that of pieces of wood from 9.5m level, 20600±400y.B.P. (KURI 186, T. SAKATA). These ¹⁴C dates reinforce the correlation of our pollen zones to the zones FG, RI and RII.

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第1報で明らかにされた各種の火山灰土壤について, 母材と土壤生成の関係を研究した結果, 母材の累積的堆積状態が, 各地形面での土壤生成に密接に関係していることが明らかにされた. また本研究では, テフラ中の強磁性鉱物の化学組成が, テフラの識別に有効であることも明らかにされた.
研究対象とされた村崎野軽石層までのテフラは, 上部より1,000～5,000年と推定される石英安山岩質の累積火山灰 (金ケ崎および村崎野面の黒ボク土のA₁層), 10,000～数万年と推定される安山岩質の累積性火山灰 (例えば村崎野面の黒ボク土のIIB_b層), および数万年ないしそれ以上の安山岩質の火山灰と村崎野軽石層 (例えば村崎野面の黒ボク土のIIIA_b層以下) よりなっている. そして, このような累積性の母材は, 間けつ的な降灰によって供給されたため, それぞれかって地表風化を受け, 下部ほどよく風化していることが分った.
金ケ崎段丘上の火山灰は, すべて若い累積性火山灰 (1,000～5,000年) を母材とする若返りタイプのA₁層を形成している. そして火山灰層の下位には扇状地を構成する堆積物が存在する.
村崎野段丘では母材の人為的混合, 削剥, 移動再積が各土壤の生成に密接に関係している. この段丘上の黒ボク土のA₁層は, 金ケ崎段丘の黒ボク土のA₁層の母材に加えて, 下位のIIB_1b層の火山灰も一部含まれている. しかもこれらの母材が人為的によく混合されていることが分った. 淡色黒ボク土-IIは, 人為の影響を強く受けて, 黒ボク土のA₁層に相当する母材が削剥されて生成している. 一方多湿黒ボク土は, 再積性土壤である.
西根段丘の地域の土壤は, 地形の開析が進んでいるため, 頂面 (summit) から背斜面 (backslope) までは削剥土壤である淡色黒ボク土-IIが, また斜面の下部 (footslope) から谷底部 (valley bottom) までは再積性の多湿黒ボク土であることが明らかとなった. なお本地域の火山灰土壤の生成には, 地形と母材に加えて, 人為や植生もまた密接に関係していることが, 考察された.

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The mechanical analysis, the heavy mineral analysis and the measurement of roundness of rourndnest of the sand grains of Niigata Sand Dunes indicate that there are some differences of their results among the Recent Dunes I, II and III, and also that there is some regional variation within each row of these dunes. We considered the process of the formation of the Recent Dunes I, II and III in the light of these facts as well as the topographical features of the dunes which we had already reported. It is believed that the sand which was supplied by the Shinano River and the Agano River played the most important role in the formation of Niigata Sand Dunes.

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