Archaeological sites along the Taishaku River, collectively called the Taishaku-kyo sites, have yielded abundant mammalian remains of Late Pleistocene and Holocene Age. Paleontological data on the remains hitherto obtained from four representative sites, the Kannondo, Domen, Anagami and Mawatari sites, are compiled, in order to confirm the biostratigraphic distribution of mammals.
About 69% of the well-identified forms known from these sites are extant species which occur in the modern mammal community of this area. Among them, most species are recovered from both Late Pleistocene and Holocene horizons, and thereby they are considered to have continuously inhabited this area since the Late Pleistocene. On the other hand, about 19% are exotic forms which are now absent from this area, but occur in other areas. Because each of them disappears at various horizons, they are assumed to have become extinct in this area at various times ranging from Late Pleistocene to Holocene. The remaining 12% are extinct forms, which occur in the Late Pleistocene horizons only. This suggests that they disappeared from this area by the end of the Late Pleistocene.
The horizons for the disappearance of these exotic and extinct forms are assigned to approximately 32, 000-21, 000yrs BP (Panthera cf. pardus), 21, 000-16, 000yrs BP (Anourosorex japonicus, Ursus sp. and elephantids), 16, 000-12, 000yrs BP (Microtus epiratticepoides and M. cf. brandtioides), 10, 000yrs BP (Sinomegaceros yabei) and 6, 000-5, 000yrs BP (Lynx lynx). Although further accumulation of well-dated records is required, these dates are possibly coincident with the approximate timing of extinction of these mammals in Honshu.

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The median diameter (Md) of grain size distribution of three loess-paleosol sequences from the Loess Plateau of central China has provided a critical evidence for the variation of winter monsoon intensity in this region during the last 130, 000 years. The median grain size (Md) value is regarded as a direct measure of the intensity of the winter monsoon which transported dust grains; the higher the Md value, the stronger the winter monsoon. Median grain size curves of the three sections indicate presences of three distinct periods of finer dust grains separated by two intervals of coarser dust grains. The median grain sizes were finer during the periods of 130, 000-73, 000yrs BP, 60, 000-25, 000yrs BP and 10, 000-5, 000 yrs BP, which indicates that the winter monsoon were weak during these periods. In the intervals of 73, 000-60, 000yrs BP and 25, 000-10, 000yes BP, the Md values increased progressively, reflecting that winter monsoon were strong. At about 18, 000yrs BP, the median grain size shows a peak of coarsening, implying an extremely intensified winter monsoon during the Last Glacial maximum. Our results demonstrate that the median grain size is an excellent index for the winter monsoon variations during the Late Quaternary.

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A volcanic ash and two different drift pumices were detected in the Upper Pleistocene Katanishi Formation, Oga Peninsula, Akita Prefecture, Northeast Honshu, Japan. On the basis of the petrographic and stratigraphic studies of these tephras, it is concluded that the ash is the Aso-4 ash ejected at about 74ka BP from the Aso Caldera, Central Kyushu, one of the most prominent marker tephras of the Late Pleistocene in Japan; one of the drift pumices which lies just on the Aso-4 ash on the Anden Coast is identified as the Aso-4 pyroclastic flow deposits, and the other, found in the uppermost part of the Formation at its type section, is identified as Sambe-Kisuki pumice fall deposits which erupted at about 80-90ka BP from the Sambe volcano in Shimane Prefecture, San' in District, Southwestern Honshu, Japan.
Based on this study, the following stratigraphic and paleo-oceanographic evaluations are obtained. The Katanishi Formation, from which the Toya ash (90-100ka) had been detected, is ascertained to be correlated with the Obaradai Formation in Southern Kanto, which is one of the standard Quaternary areas in Japan. The correlation with the Shimosueyoshi Formation, which was deposited during the last high stand of sea level in the Pleistocene in Southern Kanto, should be defined in the Quaternary sequence underlying the Katanishi Formation. The existence of drift pumice derived from Southwestern Japan indicates that the northeastward ocean current had been flowing in the Japan Sea at about 80-90 and 70ka BP.

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The Kisogawa Volcanic Mudflow Deposit (kmf), derived from the Ontake Volcano, has been found to be distributed on terraces around the Ontake Volcano down to the northeastern part of the Nobi Plain, along the Kiso River for a distance of more than 144km. Therefore, the kmf has been used as a key bed for comparing and correlating the upper Pleistocene of mountainous regions with those of coastal regions in Central Japan.
Six wood trunks have been collected from the kmf and two wood chips from the clay bed immediately overlaid by the kmf, at Nishikoori, Yaotsu-Cho, Gifu Prefecture. The sampling site is located in the east end of the Minokamo Basin, as shown in Fig. 1, where the kmf constitutes the upper part of the Middle Terrace Deposits of the Kiso River (Figs. 2 and 3).
Radiocarbon ages of the wood samples have been measured by a Tandetron accelerator mass spectrometer at the Dating and Materials Research Center, Nagoya University. ¹⁴C ages of six wood samples from the kmf range from 48, 750 to 51, 840yrs BP, except for a rather younger age of 43, 520yrs BP (KD-4; Table 1). The average of the older five dates is 49, 850±420yrs BP. The two wood chips from the clay layer below the kmf show ¹⁴C ages of 47, 280 and 51, 980yrs BP (Table 2), which are almost equal within margins of error to those of the log samples from the kmf. Based on these dates, it is concluded that the kmf was formed about 50, 000 years ago. This study, resulting in a much older ¹⁴C age of the kmf than the age generally accepted (ca. 27, 000yrs BP), enforces a revision of the chronology of Late Pleistocene deposits and tephras, which have been accumulated on terraces along the Kiso River and buried under the Nobi Plain.

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