FY 1995

Tsunami runup distribution generated by the July 12, 1993, Hokkaido-Nansei-Oki earthquake

Bernard, E.N., and F.I. González

In Proceedings, 26th Meeting of the U.S.-Japan Cooperative Program in Natural Resources Panel on Wind and Seismic Effects, Gaithersburg, MD, 16–20 May 1994, 335–343 (1994)

The Hokkaido-Nansei-Oki earthquake produced one of the largest tsunamis in Japan's history. Tsunami vertical runup measurements varied between 15 and 30 m over a 20-km portion of the southern part of Okushiri Island with several 10-m values on the northern portion of the Island. Along the west coast of Hokkaido, no survey values exceeded 10 m, but damage was extensive at several coastal towns. Given the sudden onset of the tsunami and its high energy, it is amazing that more people were not killed. We also observed that the seawall at Aonae was effective in reducing runup amplitudes.