3. 東南梅地震に就いて : 特に震害と餘震の分布

The great earthquake that occurred off the Pacific coast of the To-Nan-Kai, at 13h 36m, December 7, 1943, was so strong that it was felt sensiblly throughout Honshu, Sikoku and Kyushu. Serious damages were caus d to ordinary houses and other structures in the large area, by not only earthquake shocks but also the tunami, which advanced against the south coast of the Kii peninsula. According to statistical investigation of damages, 54,000 houses were demolished and about 1,000 persons were killed. This paper treats, the relation between destruction-rate of dawelliug house and the character of earth-ground of the stricken area. Destruction-rate shows remarkablly high in the alluvial region, specially in he reclaimed land from the sea. A component of micro-seismograph was installed at four temporary stations, namely, Okazaki, Toyohasi, Yokkaiti and Uziyamada. As a result of the seismic observation, hypocentres of forty after-shocks which are a part of earthquakes occurrdd during February, 14, ～March, 20, 1944, were determined by use of duration of preliminary micro-tremors. As shown in figs. (6) and (7), epicenters of after-shocks are distributed only in the west side of the in (UV) that passes on two epicentres of the To-Nan-Kai and Mikawa earthquakes. Moreover, new main fault paralels or coincides with the UV-line. These facts and o her examles of after-shock at the occasion of strong earthquakes lead us to such a conclusion that the Mikawa earthquake on January 13, 1944, is an after-shock of the To-Nan-Kai earthquake