CHANGE IN SEDIMENT CHARACTERS AND BATHYMETRY IN MATSUKAWAURA INLET DUE TO THE TSUNAMI ON MARCH 11, 2011

Abstract

 The 2011 off the Pacific coast of Tohoku Earthquake caused catastrophic damage along coastal area in Fukushima Prefecture, Japan on March 11, 2011. The big tsunami generated by the earthquake was as high as 14m and caused significant change in sediment and bathymetry in Matsukawaura inlet in Soma city, Fukushima. The Matsukawaura is scenic and important fishing area. Therefore, sediment samples were collected at 147 points and water depths were measured at 268 points as an emergency environmental assessment. In general, sediment becomes coarse in the most of area except northwest and southeast parts of the inlet. In addition, it is observed that large quantity of finer sediment in Matsukawaura were transported and deposited inland. Water depth become deeper and the most of tidal flat were lost.