[S04-4] Historical and macroseismic studies of earthquakes IV

[S04-4-02] Document database for historical earthquakes around Tokyo area

^○Kenji Satake¹, Jun Muragishi¹, Akihito Nishiyama¹, Masaharu Ebara², Toshifumi Yata³, Takeo Ishibe⁴ (1.Earthquake Research Institute, University of Tokyo, Japan, 2.Historiographical Institute, University of Tokyo, Japan, 3.Faculty of Humanities, Niigata University, Japan, 4.Association for the Development of Earthquake Prediction, Tokyo, Japan)

The Tokyo metropolitan area has suffered many damaging earthquakes, since the beginning of shogunate capital in Edo (former name of Tokyo) in 1703. During the Edo period (1703-1867), the 1703 Genroku Kanto earthquake and the 1855 Ansei Edo earthquake caused the severest damage; the casualties were estimated as 10,000 for each event. The 1703 earthquake is considered to be an M~8 plate-boundary earthquake, similar to the 1923 Kanto earthquake which caused the worst disaster in Japan, and the damage was documented in wide area. The 1855 earthquake (M~7) seems to have occurred just beneath Tokyo, because the damage was mostly limited in Edo city.
We constructed the full-text digital document database for these earthquakes, as well as other smaller earthquakes that caused damage in Edo and suburbs. For the 1703 earthquake, the total number of records is 378, including memorial monuments of tsunami victims in Boso peninsula. For the 1855 earthquake, numerous documents including caricature were published, and only a part of them has been included in the database. The database contains about 1200 records from other 35 earthquakes in and around Tokyo area in the Edo period. For about a half of them, historians emended the descriptions and assigned the reliability of documents.
The database has similar format as the Online Database of Historical Documents in Japanese Earthquakes and Eruptions in the Ancient and Medieval Ages (Ishibashi, 2009) which covers the earthquakes between 417 and 1707 with about 3000 records.