The Ansei Nankai quake (安政南海地震, Ansei Nankai Jishin) was an 8.4 magnitude earthquake which struck on December 24, 1854. Over 10,000 people from the Tōkai region down to Kyushu were killed.[1]
The Hōyo Strait earthquake [ja] (豊予海峡地震, Hōyo Kaikyō Jishin) was an M7.4 intra-plate earthquake in Hōyo Strait affecting Kyushu and Shikoku on December 26, 1854. It affected nearby area more than the two megathrust earthquake that happened in the previous few days.[2][3][4]
The Ansei Edo quake (安政江戸地震, Ansei Edo Jishin) was a Ms 7.0[5] earthquake which struck Edo (modern-day Tokyo) on November 11, 1855. ~120 earthquakes and tremors in total were felt in Edo in 1854-55. The great earthquake struck after 10 p.m.; roughly 30 aftershocks continued until dawn. The epicenter was near the mouth of the Arakawa River. Records from the time indicate 6,641 deaths inside the city, and 2,759 injuries; much of the city was destroyed by fire, leading many people to stay in rural inns. Aftershocks continued for ~20.[1] This quake was a particularly destructive deep thrust quake caused by a giant slab of rock stuck between the Philippine Sea Plate and the Pacific Plate.
The earthquakes were blamed on a giant catfish (Namazu) thrashing about.[by whom?]Ukiyo-e prints depicting namazu became very popular around this time.
An1856 earthquake off Hachinohe coast [ja] was estimated to be a megathrust earthquake with Magnitude 7-8, with tsunami recorded, however damage was relatively few.[7]
^ abc_____. (2007). "Great Earthquakes of Ansei" (安政大地震, Ansei Daijishin)inHistorical Encyclopedia of Great Edo (大江戸歴史百科, Ō-Edo Rekishi Hyakka), p. 253.
