Earthquakes near Karatsu through history

The deadliest was not the strongest: an estimated magnitude 6.4 on May 21, 1792 (Kyusyu Island), for which NOAA records 15,030 deaths. NOAA’s list of significant earthquakes has 9 here, back to AD 744. NOAA records deaths in 13 of the events here, 18,962 in all. The latest on NOAA’s list is a magnitude 7 on April 15, 2016 (6 km ESE of Kumamoto, Japan). NOAA’s record here begins on June 30, 744 with a tsunami (Sw. Kyushu Island). It grows thinner going back: 2 of the 9 significant earthquakes NOAA lists here are from 1927 on. NOAA lists 6 tsunamis that began within 100 km of Karatsu, and 5 from elsewhere that reached it with deaths or a metre of water or more. The highest water NOAA records here was 55 m, on May 21, 1792. The deadliest here came on June 30, 744 from a magnitude 6.4 earthquake (Sw. Kyushu Island): NOAA’s runup records count 1,520 deaths within 100 km of Karatsu. NOAA lists 5 significant eruptions of one volcano within 100 km of Karatsu. The largest was Unzendake on April 15, 1664, at 2 on the volcanic explosivity index. It killed 30 people by NOAA’s count.

• April 15, 2016Earthquake · M 7.06 km ESE of Kumamoto, Japan · 273 deaths (NOAA)USGS · NOAA NCEI · Wikipedia
• November 10, 1909Earthquake · M 7.518 km SE of Honmachi, JapanUSGS · NOAA NCEI
• May 21, 1792Earthquake · M 6.4 (est.)Kyusyu Island · 15,030 deaths (NOAA)NOAA NCEI
• May 21, 1792Tsunami · 55 m hereShimabara Bay, Kyushu IslandNOAA NCEI · Wikipedia
• April 15, 1664Eruption · VEI 2Unzendake · 30 deaths (NOAA)NOAA NCEI · Wikipedia
• June 30, 744TsunamiSw. Kyushu Island · 1,520 deaths here (NOAA)NOAA NCEI

• An event counts for Karatsu 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