FIELD SURVEY AND NUMERICAL ANALYSIS OF 2011 TOHOKU EARTHQUAKE TSUNAMI IN THE NORTHERN PART OF MIYAGI, JAPAN

Abstract

The field survey results obtained by the team of authors in the north of Miyagi Prefecture are summarized referring to a part of the survey results by other teams of the 2011 Tohoku Earthquake Tsunami Joint Survey Group. The inundation height above sea level was measured using a laser range finder with a reflection prism. The inundation height was generally larger at bay heads, as well as cave tips, except several points, which were sheltered by a peninsula or had a tapering area. The tsunamis reached inland far away from the sea along valleys and rivers. Not only steel frame buildings but also many reinforced concrete buildings were collapsed in Onagawa Town. According to the numerical simulation, the first tsunami from the west coast and the second tsunami from the east coast should come together in Utatsusaki Peninsula, which is consistent with the interviews to survivors.