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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The distribution of Andosols and their relation to topography were clarified in the previous paper. In the present report the relationship between parent materials and soil formation is discussed.
Cumulative tepha layers from the top to the Murasakino pumice are divided into three groups; younger dacitic ash (1, 000 to 5, 000 years B.P.), older andesitic ash (10, 000 to 20, 000 years B.P.) and Murasakino pumice (20, 000 or more years B.P.). Each ash group also consists of several ash layers. Since most tephra layers were brought to the surface intermittently, they were subjected to surface weathering. Therefore, the degree of weathering of hypersthene and/or augite in the Andosols shows a tendency to become greater with the depth of soil profiles.
All the Andosols on the Kanngasaki terrace show the rejuvenation type of humus horizons formed of younger dacitic ash which covered the alluvial deposits.
The formation of Andosols on the Murasakino terrace was found to be closely related to the depositional features of the parent materials, to the mixing of the soils atrificially and to the truncation and redeposition of the soils. Tephra layers from the top to the Murasakino pumice were found in the profile of Normal Andosol. However, the Al horizon of this Andosol contains more or less the parent material belonging to the subsoil in addition to the parent materials which are common to the same horizon of Normal Andosol on the Kanagasaki terrace. It was noted that these materials were well mixed. Light-colored Andosol (II) was formed after the truncation of the Al horizon of Normal Andosol on the same terrace. Aquic Andosol was formed by the redeposition of eroded materials in the valley bottom.
Light-colored (II) and Aquic Andosols on the Nishine terrace were formed by truncation and redeposition, respectively, as observed in the Murasakino terrace. However, the formation of these soils was found to be more advanced on the Nishine terrace which is more strongly dissected.

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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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