TSUNAMI PROPAGATION INTO RIVERS IN TOHOKU DISTRICT

Abstract

On March 11, 2011, the Great East Japan Earthquake generated huge tsunami waves. Then, tsunami propagation occurred and expanded the flooded area. Tsunami propagation distance was collected and analyzed to estimate the area where we need the defense. It was found tsunami propagation distance in river is about 1.2 to 4.5 times as long as land area and, there is a good correlation between propagation distance in rivers and the bed slope. Furthermore, the dissipation coefficient of tsunami height was successfully estimated by applying the empirical equation and the general relation of wave height to distance.