[MIS01-03] Geological features of tsunami deposits associated with the 1983 Nihonkai-chubu earthquake in pine-based windbreak forests of Noshiro City and Happo Town in Akita Prefecture, Japan
Keywords:The 1983 Nihonkai-chubu earthquake, Tsunami deposit, Diatom
Since there exist few reports of tsunami sediments with specific ages in Japan, they are an important historical record of past disasters and are geologically significant; the samples can be used to study the magnitudes and inundation processes of tsunamis. It has been noted that tsunami deposits lose their sedimentary structures and constituents with time and changes in weather conditions. In this work, we conducted geological surveys along the coastal areas of Noshiro City and Happo Town to determine the distribution of deposits caused by the tsunami due to the 1983 Nihonkai-chubu earthquake. In this presentation, we will report basic geological features such as the planar distribution of the tsunami deposits as well as changes in their thickness, grain size distributions, and fossil diatom assemblages.