[H-CG37_30PM1] 堆積・侵食・地形発達プロセスから読み取る地球表層環境変動

[HCG37-01] 湖沼に残された津波堆積物の形成過程と空間分布：水槽実験による検討

*山口 直文¹、関口 智寛² (1.茨城大学広域水圏環境科学教育研究センター、2.筑波大学アイソトープ環境動態研究センター)

キーワード：津波堆積物, 水槽実験

A series of flume experiments were performed to examine the sedimentary process and distribution of tsunami deposits in coastal lakes. In the experimental program, a fixed slope of 1/20 and terrestrial area including a pool as a coastal lake were installed, and tsunami-like solitary wave was generated. The tsunami flow transported sediments from a sand bed placed on the slope, and deposited them on the terrestrial area. When the tsunami flow irrupted into the pool, hydraulic jump was occurred. In the area where the hydraulic jump made turbulence, little sediment deposited. Thus, the distribution of the tsunami deposits in the pool did not always show the thinning-landward trend in the present experimental series. The dependence of the amount of sediments on magnitude of tsunami waves was more pronounced in the pool than the land area.