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We used cores drilled up to depths of m from the central Kanto Plain, Japan, to examine the stratigraphy of the Kazusa and Shimosa groups, and correlate marine intervals with marine oxygen isotopic stages (MIS). Both groups contain sediments from the upper Pliocene (Gauss Chronozone), and the lower to upper Pleistocene. We recognized an unconformity in the Kazusa Group at around . Ma, which represents a . -. Myr hiatus in the sequence. Both groups comprise cyclic deposits of shallow marine and terrestrial sediments, and there was no significant hiatus after . Ma in either group. From the depths of correlated marine intervals, we infer that this part of the Kanto Plain, including the cities of Kuki and Kasukabe, was a center of tectonic subsidence around . Ma.

Pollen data from the upper part of the Tanaka Formation in the Higashinada -m drill core, obtained from Kobe City, southwest Japan, enable the construction of a pollen biostratigraphy and detailed record of paleoenvironmental change during the Middle Pleistocene.In this study, sediment samples were collected at ca. -m intervals from the upper part of the Tanaka Formation, which approximately corresponds to the upper Osaka Group. This formation, which is the hypostratotype for the Pleistocene stratigraphy in the Osaka sedimentary basin, consists mainly of fluvial and lacustrine sediments intercalated with marine clay beds. The fossil pollen assemblages in the marine clay beds are dominated by tree and shrub pollen belonging mainly to temperate and cool-temperate deciduous broad-leaved and temperate evergreen coniferous tree taxa, accompanied by pollen of warm-temperate deciduous coniferous and evergreen broad-leaved tree taxa. The pollen assemblages within non-marine sediments that immediately underlie each of the marine clay beds are dominated by herbaceous taxa and tree taxa such as Alnus; they also contain Pteridophyte spores.The pollen biostratigraphy from Ma to Ma marine clay beds in the Higashinada core comprises pollen assemblage zones and superzones: the Quercus-Metasequoia, Fagus-Quercus, CryptomeriaFagus, Cyclobalanopsis-Sciadopitys, and Pinaceae-Cryptomeria, in ascending stratigraphic order.At the time of the Quercus-Metasequoia Superzone, the paleovegetation consisted of warm-temperate deciduous broad-leaved forest. Subsequently, temperate evergreen conifers show a gradual increase in abundance. At the time of the Fagus-Quercus Superzone, the paleovegetation consisted of mixed warm-temperate deciduous broadleaved and temperate evergreen conifer forest. The CryptomeriaFagus Superzone is characterized by alternating periods of temperate evergreen conifers and temperate deciduous broad-leaved trees. The Cyclobalanopsis-Sciadopitys Superzone is characterized by warmtemperate evergreen broad-leaved forest accompanied by temperate evergreen conifers in the hinterland, and the Pinaceae-Cryptomeria Superzone is dominated by temperate evergreen coniferous forest. Abstract