12/02/1611 | 1611 Keicho Earthquake


As one of the major historic Japanese tsunami earthquake, there are still aspects unclear. So far the 1611 Keicho earthquake has been located to the northern end of the Japan Trench affecting especially the coasts of Eastern Honshu. However, following the findings of Nanayama (2003) and Sawai (2008), there was an unusually large tsunami earthquake offshore Hokkaido and Kuril Islands. Based on sedimentary records this event was dated to the early 17th century. Assuming that this tsunami was much larger than any instrumentally recorded earthquake today, a magnitude of at least 8.5 was assumed.

Events in the same region
Date Title Region Preferred Magnitude Quality*
1150s 12th Century Hokkaido Paleo-Earthquake Hokkaido 7.9 D
1611 Dec 02nd 1611 Keicho Earthquake Hokkaido 8.5 C
1677 Apr 13th 1677 Sanriku Earthquake Hokkaido 7.9 C
  • GHEA (GHEC v1.0) -Albini P., Musson R.M.W., Rovida A., Locati M., Gomez Capera A.A., and Viganò D. (2014). The Global Earthquake History. Earthquake Spectra, May 2014, Vol.30, No.2, pp. 607-624. http://doi.org/10.1193/122013EQS297 - Link
  • Nanayama e al. (2003) -Nanayama, F., Satake, K., Furukawa, R., Shimokawa, K., Atwater, B. F., Shigeno, K., & Yamaki, S. (2003). Unusually large earthquakes inferred from tsunami deposits along the Kuril trench. Nature, 424(6949), 660-663. - Link
Event Characteristics
Preferred Magnitude 8.50 (8.10-9.00)
Epicenter 42.500°N, 146.000°E
Depth unknown
Tsunami yes
Paleo-Event no
Quality of Evidence C

Magnitude Range
Year Reference Magnitude
2014 GHEA (GHEC v1.0) 8.1
2003 Nanayama e al. (2003) 8.5 (8.3-9)

This table lists some of the most relevant publications in estimating the moment magnitude of this earthquake. If you think there are other important or new publications, please get in contact.