LONG-TERM SEDIMENT TRANSPORT IN KUZURYU RIVER AND KAETSU COAST UNDER HOLOCENE SEA LEVEL VARIATION

Morika Ohmura, Shinji Sato

Abstract


The Kaetsu Coast has been facing problems of coastal erosion and accumulation of sediments in dams and harbors. This study aims to investigate sediment transport and its long-term changes considering sea level variation in the Holocene. Numerical calculation of waves and nearshore currents, together with analysis of physical properties of sand particles such as diameter, color and thermo-luminescence were conducted to estimate the source and transport direction of sediment over geological time scale. It is found that the changes in the nearshore currents around the Kuzuryu River mouth and sediment supply from old dunes onto the coast north of the Kuzuryu River mouth are essential in understanding the sediment movement in the watershed scale.

Keywords


regional sediment transport; sea level variation; coastal erosion

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References


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DOI: https://doi.org/10.9753/icce.v34.sediment.57