2023 Volume 76 Pages 233-250
In the present study, we investigated the disaster on September 7th, 1092 (on the Julian calendar) in Echigo (present Niigata Prefecture), listed as possible earthquake and tsunami disaster by previous studies. Almost all historical materials which describe the occurrence of earthquake and tsunami were revealed to be documented in and after the late Edo period, more than 600 years after the 1092 event. In all these materials, the date of occurrence and tangible damage due to ground shaking were not clearly described. Therefore, there are no clear evidence that the descriptions on these historical materials indicate the occurrence of earthquake and tsunami on that day. On the other hand, highly reliable contemporary historical materials (e.g. contemporary diaries by court nobles) documented the occurrence of meteorological hazard and disaster on that day such as strong wind, storm surge, flood, and damage on building structure to the Ise Shrine in present Mie Prefecture. In these contemporary materials, the occurrences of earthquake and tsunami on that day were not described. These results suggest that the 1092 disaster was not an earthquake and tsunami disaster but a meteorological hazard and disaster.
