5:15 PM - 6:30 PM
[MIS27-P02] Historical materials of unlisted destructive earthquakes at Izu-Bonin Islands in the Meiji period: the 1873 Toshima earthquake and so on
Keywords:historical earthquake, the Izu-Bonin Islands, the 1873 Toshima Island earthquake, the 1885 Niijima Island and Shikinejima Island earthquake, the 1885 Bonin Islands earthquake
Destructive earthquakes that have occurred in the vicinity of Japan from ancient times are summarized in catalogs such as "Chronological table of earthquakes" in “Chronological scientific tables” (National Astronomical Observatory of Japan, 2020), and “Materials for a comprehensive list of Japanese destructive earthquakes 599-2012” (Usami et al., 2013). Usami et al. (2013) include earthquakes that have caused damage or changes to houses, artificial structures, or the ground. I investigate records of earthquakes that caused damage to the Izu-Bonin Islands in the Meiji period (1868 -1912) and are not listed in Usami et al. (2013).
In this study, I focus on an earthquake that occurred in 1873 (Meiji 6) and caused damage to Toshima Island (Present Toshima Village, Tokyo) in the northern Izu Islands. The earthquake caused damage to temples and shrines in Toshima Island [Toshima Village (1996a)] and caused landslides [Toshima Village (1996b)]. As for the date of the earthquake, the records in Toshima Island say "Meiji 6, 6th month, 8th day " [Toshima Village (1996a)]. These records exceptionally used the Japanese calendar system, although 1873 was the year when the Japanese calendar (lunar calendar) was switched to the Western calendar in Japan. "Meiji 6, 6th month, 8th day" on the Japanese calendar is 1873 July 2 on the Western calendar. In the study, I survey other historical records about the earthquake.
In addition, I examine the earthquake in the Izu Islands on 1885 (Meiji 18) October 26, and the earthquake in the Bonin Islands on 1885 (Meiji 18) November 4. In the former earthquake, several coastal cliffs of Niijima Island and Shikinejima Island (Present Niijima-mura, Tokyo) in the northern Izu Islands collapsed, and the channel of the water source in Shikinejima Island was blocked. In the latter earthquake, landslides occurred in the Bonin Islands such as Chichijima Island (Present Ogasawara Village, Tokyo). Neither earthquake is not listed in Utsu (1979), which compiled M6.0 or greater earthquakes and smaller destructive earthquakes in and around Japan from 1885 to 1925.
In this study, I focus on an earthquake that occurred in 1873 (Meiji 6) and caused damage to Toshima Island (Present Toshima Village, Tokyo) in the northern Izu Islands. The earthquake caused damage to temples and shrines in Toshima Island [Toshima Village (1996a)] and caused landslides [Toshima Village (1996b)]. As for the date of the earthquake, the records in Toshima Island say "Meiji 6, 6th month, 8th day " [Toshima Village (1996a)]. These records exceptionally used the Japanese calendar system, although 1873 was the year when the Japanese calendar (lunar calendar) was switched to the Western calendar in Japan. "Meiji 6, 6th month, 8th day" on the Japanese calendar is 1873 July 2 on the Western calendar. In the study, I survey other historical records about the earthquake.
In addition, I examine the earthquake in the Izu Islands on 1885 (Meiji 18) October 26, and the earthquake in the Bonin Islands on 1885 (Meiji 18) November 4. In the former earthquake, several coastal cliffs of Niijima Island and Shikinejima Island (Present Niijima-mura, Tokyo) in the northern Izu Islands collapsed, and the channel of the water source in Shikinejima Island was blocked. In the latter earthquake, landslides occurred in the Bonin Islands such as Chichijima Island (Present Ogasawara Village, Tokyo). Neither earthquake is not listed in Utsu (1979), which compiled M6.0 or greater earthquakes and smaller destructive earthquakes in and around Japan from 1885 to 1925.