Holocene Paleoenvironments and the Highest Sea-level Based on the Diatom Assemblages in Minuma Lowland, Saitama Prefecture

Abstract

Minuma Lowland is an erosional valley that lies in the Oomiya Upland, Saitama Prefecture. The author has investigated the stratigraphy of the Holocene deposit filling the erosional valley. The surface deposit is about 6.5 meters thick and is composed of peat and gray clay. This is underlain by a sand bed over 6-15 meters thick. Moreover, the author has investigated the Holocene Paleoenvironments and the highest sea level based on the diatom assemblages contained in their deposits in the Minuma Lowland. Diatom assemblages from this area showed that the highest level of the sea attained was at least +3.9-+4.1 meters above sea level. The highest stage of the sea level is probably younger than about 5950-5540y.B.P.