第四紀層序学  [in Japanese] Quaternary stratigraphy  [in Japanese]

Since Quaternary Researchin Japan (KOBAYASHI, 1968) was published at the 75th anniversary of Geological Society of Japan, stratigraphical research on the Japanese Quaternary has progressed steadily. Actually a number of papers, volumes and geological maps concerning Quaternary stratigraphy have been published during the last fifteen years. This paper outlines and/or reviews the progress of studies on the following three subjects. 1. the Plio-Pleistocene, 2. the Middle-Upper Pleistocene and the Holocene, 3. Tephrostratigraphy. 1. Outlines of the Plio-Pleistocene in Hokkaido, Aizu, Niigata, Kinki, Kuchinotsu, Oga, Boso, Kakegawa and Ryukyu are described on the basis of data accumulated mainly by litho-, bio- and magneto-stratigraphical studies. The information on the Plio-Pleistocene boundary, however, still shows discrepancy between the conclusion induced from marine strata and that from mainly terrestrial strata. 2. The progress of studies on the Middle-Upper Pleistocene and the Holocene is remarkable in two fields, Shimosueyoshi terrace problem and late Quaternary environment. It is expected that the lower limit of the Upper Pleistocene in Japan will be fixed in relation to Shimosueyoshi terrace, and also human history of the Late Pleistocene will be traced by excavation around Lake Nojiri. 3. Tephra layers in Quaternary sediments are valuable for studies on stratigraphy, volcanology, geomorphplogy and pedology, because these essentially mark an extermely short span of time in geologic history and are of wide distribution. Regional stratigraphy, wide spread tephras, idetification of tephras, and relationship between tephras and volcanic activities have been vigorously studied from the tephro stratigraphical viewpoint. Therecent progress of research on tephrostratigraphy is described.