Abstract
The Mikawa earthquake (M=6.8) occurred on January 13th in 1945. This is about one month after the Tonankai earthquake (M=7.9). This event has a small number of Nk, which was defined as the number of totally collapsed wooden houses / the number of death tool, and it occurred during the Second World War. The data summarized by Iida in 1985 has been used for discussing the damage from the Mikawa earthquake, which was estimated from the maximum value of the damage data summarized for the counties. A part of them dose not have municipal data which cannot be found now. In this study, we re-evaluate the data of municipalities from Security Division of Aichi Prefecture of January 14, 1945 and the others for the estimation of the seismic intensity distribution in JMA scale. As a result, seismic intensities in the Okazaki basin, which is alluvial lowland, are relatively larger than those of the Hazu hill zone, irrespective of the distance from the Fukozu fault, which associated surface fault breaks with the Mikawa earthquake. This shows that the influence of the ground condition is the largest factor for the strength of seismic intensity and earthquake damages. On the other hand, it can also be found that the Nk value is especially small in the municipalities including the trace of the Fukozu fault. The cause of the small Nk value will be necessarily discussed in relation to the characteristics of the strong ground motion close to the earthquake fault.
