Abstract
14C dating, sedimentary facies analysis, volcanic ash analysis, pollen analysis, diatom analysis and radiolaria analysis were carried out to clarify the Quaternary stratigraphy on the 150 m core, drilled in 1981, in the campus of Hokkaido University, central part of Sapporo. Our investigation leads to the following conclusions. 1) The core is divided into nine formations, HU-1 to HU-9. The HU-1 to the HU-3 in 150−75 m depth are correlated to the Shimonopporo Formation of the early to middle Pleistocene, the HU-4 and the HU-5 in 75−35 m depth to the Momijidai Formation of the late Pleistocene, the HU-6 in 35−34 m depth to the Konopporo Formation of the late Pleistocene, the HU-7 and the HU-8 in 34−7.8 m depth to the Sapporo Fan Deposits of the late Pleistocene, the HU-9 in 7.8−0 m depth to the Holocene. 2) Identification of the cold stage and warm stage in the HU-4 and HU-5, last interglacial stage deposits, causes the possibility of accurately comparing to the deposits in the southernmost part of Ishikari Depression. 3) Peat bed intercalated in 130 m depth, 119 m below sea level, in the correlative of Shimonopporo Formation of the core is correlated to the peaty deposits which exist at about 110 m below sea level in the nearby two boreholes, and peat beds which intercalated under the Ishikari Coastal Plain within the range from 102 m to 126 m below sea level in the correlative of the Shimonopporo Formation.
