DEVELOPMENT OF AN ISOLATED SAND BAR DUE TO INSTABLITY MECHANISM AROUND NAGASE RIVER MOUTH IN LAKE INAWASHIRO

Abstract

 On the lakeshore south of the Nagase River mouth in Lake Inawashiro, typical lakeshore changes due to high-wave-angle instability can be observed, because the shoreline runs approximately in parallel to the incident wave direction. In this study, the shoreline evolution due to the instability was investigated using satellite images and field observation. As a result of the study, three sand spits were found to develop on the shoreline of the sand body, and the mean velocity of the eastward movement of sand spits were 66 m/yr. This velocity was in good agreement with the velocity of 68 m/yr calculated from the satellite images taken between 2010 and 2015.