Earthquakes near Akita through history

The deadliest was not the strongest: an estimated magnitude 7 on October 31, 1341 (Jusanko), for which NOAA records 2,600 deaths. NOAA’s list of significant earthquakes has 18 here, back to AD 850. NOAA records deaths in 15 of the events here, 4,910 in all. The latest on NOAA’s list is a magnitude 7 on March 20, 2021 (30 km E of Ishinomaki, Japan). NOAA’s record here begins on November 27, 850 with an earthquake (Yomagata, Shonai). It grows thinner going back: 6 of the 18 significant earthquakes NOAA lists here are from 1927 on. NOAA lists 6 tsunamis that began within 100 km of Akita, and 8 from elsewhere that reached it with deaths or a metre of water or more. The highest water NOAA records here was 14.93 m, on May 26, 1983. The deadliest, on October 18, 1644, killed 117 people here by NOAA’s runup records. NOAA lists 3 significant eruptions of 2 volcanoes within 100 km of Akita. The largest was Chokaisan on August 14, 1801, at 2 on the volcanic explosivity index. It killed 8 people by NOAA’s count.

• March 20, 2021Earthquake · M 7.030 km E of Ishinomaki, JapanUSGS · NOAA NCEI · Wikipedia
• May 26, 1983Tsunami · 14.93 m hereNoshiro, Japan · 47 deaths here (NOAA)NOAA NCEI · Wikipedia
• June 16, 1964Earthquake · M 7.627 km NW of Murakami, Japan · 36 deaths (NOAA)USGS · NOAA NCEI · Wikipedia
• February 7, 1897Earthquake · M 8.3 (est.)NOAA NCEI
• August 14, 1801Eruption · VEI 2Chokaisan · 8 deaths (NOAA)NOAA NCEI · Wikipedia
• October 18, 1644TsunamiHonjo, Akita · 117 deaths here (NOAA)NOAA NCEI
• October 31, 1341Earthquake · M 7.0 (est.)Jusanko · 2,600 deaths (NOAA)NOAA NCEI
• November 27, 850Earthquake · M 7.0 (est.)Yomagata, ShonaiNOAA NCEI

• An event counts for Akita when it began within 100 km of its centre, or 200 km for an earthquake of magnitude 7 or more. Damage can reach further.
• USGS counts here start at magnitude 6: the catalogue’s smaller quakes thin out going back, where few instruments listened.
• NOAA lists significant events only: earthquakes that killed, did about $1 million of damage, reached magnitude 7.5 or intensity X, or raised a tsunami, and eruptions and tsunamis by like measures. Magnitudes before 1900 are its estimates from written accounts.
• Deaths are NOAA’s total for each event, wherever people died, its tsunami and fires included. A tsunami counts the dead its runup records give for this place: NOAA’s total for a tsunami includes its source quake’s.
• A tsunami from elsewhere counts where one of its runups killed or rose a metre or more.
• Counted to October 19, 2026, as is the map. The last 30 days ask USGS again.

How the layers work, where their data comes from and what they can’t tell you: Earthquakes, live, The world through history