RECENT MORPHOLOGICAL CHANGE AT THE NARUSE RIVER MOUTH, JAPAN

摘要

The Naruse River mouth showed stable topography at least for these 46 years. However, sediment deposit occurred in July 2002, which caused difficulty in ship operation going in and out of a port located in the river mouth. In addition, the behavior of the morphology of the river mouth after the flushing of the sand spit on the left-hand side has never been observed for these 50 years. In this paper, characteristic morphological change at the Naruse River mouth is shown with the use of aerial photographs and morphological maps. Furthermore, time-variation of water-level in the river mouth is compared with tidal variation. From this analysis, it can be concluded that the river mouth closure has occurred just before the flushing of the sand bar in July 2002.