Sedimentary facies analysis for the deposited around the Pink Volcanic Ash Layer in the lower part of the Pliocene to Pleistocene Osaka Group distributed in the Southern Osaka Prefecture revealed the initiation of tectonic movement that generated folds and dome structure. Ten sedimentary facies are recognized, indicating a series of environments ranging from fan, river channel, fan delta, flood plain, estuary, lagoon, foreshore, tidal flat, Shoreface to bay mud floor. Relative sea-level curve at each study point suggests that discriminative basin subsidence occurred when the Pink Volcanic Ash Layer was deposited; The areas with a low subsidence rate evolved to present anticlines, whereas the areas with a high subsidence rate correspond to present synclines. This implies that tectonic movement that formed present fold structures has already begun in the Early Pleistocene when the Pink Volcanic Ash Layer was deposited. Reconstructed paleogeography at that time shows complicated shorelines with an arm of sea deeply projecting into the land and an elongated inlet extending north or northeast.

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The Late Quaternary fluvial terraces younger than 50ka are distributed along the middle reaches of the Shinano River about 50km long, central part of the Cenozoic Niigata sedimentary basin. Geological and tephrochronological studies on the terraces were carried out in order to clarify neotectonic movements of the study area. Four marker terraces with marker tephra layers can be identified, namely the Kawanishi terrace (50ka), Shiodono terrace (25ka), Matto terrace (13ka) and Tokamachi terrace (5ka) in descending order of elevation. Longitudinal and crossing profiles of the marker terraces show relative terrace positions from the present riverbed, and display discontinuities of relative height of terrace surfaces. The discontinuities indicate displacements of terrace surfaces after formation of the terraces. Distribution and location of active faults, approximate faults (discontinuities of terrace surfaces) and lineaments around the study area show block segmentation of based rocks with five active tectonic blocks. The block segmentation was controlled by intermittent block uplift in Late Quaternary. The relative height of each terrace from the present riverbed, shows the rate of down erosion after formation of the terrace, and hence, the rate is almost equivalent to the rate of uplift. Difference in block uplift rates, which was calculated from the relative heights between two marker terraces, reveals active and calm periods of tectonic uplift. Thus the formation processes of fluvial terraces in the study area were controlled neither by eustatic sea-level changes nor paleoclimatic factors, but by active tectonic movements during Late Quaternary.

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Here we provide new evidence suggesting that the North China is probably the locus of origin of the steppe mammoth, M. trogontherii, which had first adapted to the cool grassland environment in the mammoth lineage. The evidence comprises four teeth recently recovered from the lacustrine sediments of the Nihewan Formation at Majuangou site, Hebei Province. The sediments are dated earlier than 1.36Ma, which predates the first appearances of the steppe mammoth not only in Europe, but also in northeastern Siberia (ca.1.2-0.8Ma). Compared with all the contemporaneous mammoths, the molars of the four specimens have more plates (plate number: x17_1/2 on M_3 and x17x on M3), higher and narrower crown, thinner enamel, larger lamellar frequency and eruption angle. These characters can be regarded as advanced in the mammoth lineage, and the molars are barely indistinguishable from those of M. trogontherii from Europe not only in morphology, but also in all the measuring data. Thus they are referred to M. trogontherii herein. From chronological, distributional and morphological viewpoints, the specimens described here bridge the gaps between the earlier mammoth from China probably referable to M. meridionalis and the later M. trogontherii from the Europe and northeastern Siberia.

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Diatom biostratigraphy and tephrostratigraphy are studied for the middle to upper Miocene Uchisugawa Formation in the northeastern Shibata area, Niigata Prefecture, central Japan. The formation is composed of massive diatomaceous mudstone intercalating numerous tephra beds, four of which are widely distributed and useful for long-distance correlation. Diatom analysis was conducted for five stratigraphic sections, and diatom zones from NPD 5B through NPD 6B with nine useful diatom biohorizons are recognized in the Uchisugawa Formation. As a result, a high-resolution integrated diatom biostratigraphic and tephrostratigraphic framework is established. On the basis of sedimentation rate curves constructed for the five stratigraphic sections using the ages of the diatom biohorizons, the ages of the four widespread tephra beds, Kdg, Gtm, Skhq and Jng tephra beds, are estimated to be at 10.2-10.3Ma, 9.4-9.5Ma, 8.7Ma and 8.0-8.1Ma, respectively. Graphic correlation between the Uchisugawa Formation and the Nomura Formation in the Tsugawa area (Yanagisawa et al. 2003) confirms the correlation of tephra beds between the two areas.

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Middle Permian brachiopod fauna of the South Kitakami Belt is characterized by the mixture of both the Boreal and Tethyan elements. In the Middle Permian, the area having the Boreal-Tethyan mixed brachiopod fauna is restricted in the northern to eastern outer margin of North China (Sino-Korea), i. e., the Inner Mongolian-Japanese Transitional Zone. The South Kitakami area was probably part of a continental shelf bordering the northern to eastern margin of North China. The geographical distributions of two Boreal elements, Yakovlevia mammata (Keyserling) and Spiriferella keilhavii (von Buch), and a Tethyan element Leptodus nobils (Waagen) are summarized and illustrated.

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