Hoei earthquake

Japanese: 宝永地震 - ほうえいじしん

A huge earthquake occurred on October 4, 1707 (4th year of the Hoei Era). It is one of the largest earthquakes in Japan, and caused damage from the Kanto region to Kyushu. The epicenter was at 33.2°N and 135.9°E, and the magnitude of the earthquake is estimated to be 8.4-8.6 on the Richter scale. The damage was particularly severe in the Tokaido, Ise Bay, and Kii Peninsula. The region experienced a seismic intensity of 6-7, and Fukuroi along the Tokaido was completely destroyed, while Mitsuke, Hamamatsu, Narumi, Miya, and Yokkaichi were also partially destroyed. A tsunami was generated along the Pacific coast from the Izu Peninsula to Kyushu, the Seto Inland Sea, and Hachijojima, with an estimated height of 8-10m near Owase on the Kii Peninsula, and 3-8m in the area from the west coast of the Izu Peninsula to the Kii Peninsula and Kochi. The number of casualties was more than 5,000, and some say it was more than 20,000. The ground was noticeably uplifted and subsided, with uplifts of 1-2m in Muroto, Kushimoto, and Omaezaki, and a maximum of 2m subsidence over ^an area of about 20 km2 in the eastern part of Kochi. The Hoei earthquake is one of the subduction-type earthquakes that occur repeatedly as the Philippine Sea Plate subducts beneath southwestern Japan along the Nankai Trough. The Ansei Tokai and Ansei Nankai earthquakes of 1854, the Tonankai earthquake of 1944, and the Nankaido earthquake of 1946 occurred close together in time in the eastern and western regions bordering the Kii Peninsula, but the Hoei earthquake occurred as both the eastern and western epicenters ruptured at the same time (see Nankai earthquake).

Source: Encyclopaedia Britannica Concise Encyclopedia About Encyclopaedia Britannica Concise Encyclopedia Information

Japanese:

宝永4（1707）年10月4日に発生した巨大地震。日本最大級の地震の一つで，関東から九州にまで被害が及んだ。震央は北緯 33.2°，東経 135.9°，地震の規模はマグニチュード（M）8.4～8.6と推定されている。震害は特に東海道，伊勢湾，紀伊半島で甚大であった。この地域は震度 6～7のゆれがあり，東海道沿いの袋井は壊滅状態，見附，浜松，鳴海，宮，四日市も半壊状態だった。伊豆半島から九州にいたる太平洋岸と瀬戸内海および八丈島で津波があり，推定される高さは紀伊半島尾鷲付近で 8～10m，伊豆半島西岸から紀伊半島，高知にいたる地域では 3～8m。犠牲者数は 5000人以上で，2万人をこえるという説もある。地盤の隆起・沈降が顕著で，室戸，串本，御前崎では 1～2m隆起し，高知の東部では約 20km²が最大 2m沈下した。宝永地震はフィリピン海プレートが南海トラフに沿って西南日本の下に沈み込むため繰り返し発生する海溝型地震の一つ。1854年の安政東海地震と安政南海地震，1944年の東南海地震と 1946年の南海道地震は紀伊半島を境にした東西の領域で時間的に近接して地震が発生したが，宝永地震は東西の震源域が同時に破壊して起こった（→南海地震）。

出典　ブリタニカ国際大百科事典小項目事典ブリタニカ国際大百科事典小項目事典について　情報

<<: Defense Facilities Agency

>>: Mount Hoei