Reviewed by USGSJapan89y ago
M5.8 earthquake off the east coast of Honshu, Japan
Saturday, November 26, 1938, 10:01:05 UTC · 37.381°N, 142.559°E
A magnitude 5.8 earthquake struck off the east coast of Honshu, Japan on Saturday, November 26, 1938, 10:01:05 UTC, at a depth of 25.0 km (shallow). It is the strongest earthquake within 300 km since an M6.3 on November 25, 1938.
- Magnitude
- 5.8
- Moderate · mw
- Depth
- 25 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 75 km aftershock search area
In context
How big was it, and why here?
Energy released
8 kilotons of TNT
That is about 1/2 of the Hiroshima bomb. It released about 16 times the energy of a magnitude 5.0.
Tectonic setting
92 km
from the nearest mapped plate boundary, between the Pacific and Okhotsk plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
25 km
Shallow earthquakes (under 70 km) produce the strongest surface shaking for their size, so they are the ones most likely to cause damage near the epicenter.
Did You Feel It?
Where it was felt
No “Did You Feel It?” reports have been published for this event yet. If you felt it, you can add your report on the USGS website.
I felt it — report to USGS ↗USGS PAGER estimate
Who was exposed to shaking
USGS publishes PAGER impact estimates for significant earthquakes, usually within an hour. No PAGER estimate is available for this event.
After the main event
Aftershocks within 75 km
USGS lists 2 M2.5+ earthquakes within 75 km in the following 30 days; the largest was M7.0 on November 30, 1938. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 204 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.41933 Sanriku (Sanriku-oki) Earthquake, JapanMarch 2, 1933 · 270 km NE of this epicenter
- 7.8105 km E of Iwaki, JapanNovember 5, 1938 · 63 km SW of this epicenter
- 7.7116 km E of Namie, JapanNovember 6, 1938 · 22 km W of this epicenter
- 7.769 km ESE of Kitaibaraki, JapanMay 23, 1938 · 136 km SW of this epicenter
- 7.7116 km ESE of Namie, JapanNovember 5, 1938 · 38 km SW of this epicenter
- 7.7217 km ESE of Kamaishi, JapanJuly 6, 1905 · 179 km NE of this epicenter
- 7.6119 km SE of Kamaishi, JapanNovember 1, 1915 · 147 km N of this epicenter
- 7.6141 km ESE of Namie, JapanNovember 6, 1938 · 42 km S of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 39 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 33,566 recorded deaths. The most severe:
- 1896M8.3
Sanriku
15 Jun 1896 · 267 km away
27,122 deathsExtreme damage ($25M+)tsunami
- 1933M8.4
Sanriku
2 Mar 1933 · 270 km away
3,022 deathsExtreme damage ($25M+)tsunami
- 1828
Sandyo In Etigo
18 Dec 1828 · 270 km away
1,443 deathsExtreme damage ($25M+)tsunami
- 1793M8.3
Sanriku,Rikuzen,Rikuchu
17 Feb 1793 · 177 km away
745 deathsSevere damage ($5–24M)tsunami
- 1894M7.0
Syonai
22 Oct 1894 · 295 km away
726 deathsSevere damage ($5–24M)tsunami
- 1804M7.3
Kisakata
10 Jul 1804 · 294 km away
450 deathsExtreme damage ($25M+)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.