Reviewed by USGSJapan122y ago
M6.3 earthquake 116 km ESE of Katsuura, Japan
Saturday, February 24, 1906, 00:13:40 UTC · 34.633°N, 141.424°E
A magnitude 6.3 earthquake struck 116 km ESE of Katsuura, Japan on Saturday, February 24, 1906, 00:13:40 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M7.2 on October 24, 1905.
- Magnitude
- 6.3
- Strong · mw
- Depth
- 15 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 earthquake
In context
How big was it, and why here?
Energy released
36 kilotons of TNT
That is about 2 times the Hiroshima bomb. It released about 75 times the energy of a magnitude 5.0.
Tectonic setting
29 km
from the nearest mapped plate boundary, between the Okhotsk and Philippine Sea plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
15 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 100 km
USGS has not published any M2.5+ earthquake within 100 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 1 M5.0+ earthquake within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 10 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 12,093 recorded deaths. The most severe:
- 1855M7.0
Tokyo
11 Nov 1855 · 186 km away
6,757 deathsExtreme damage ($25M+)tsunami
- 1703M8.2
Off Sw Boso Peninsula
30 Dec 1703 · 136 km away
5,233 deathsExtreme damage ($25M+)tsunami
- 1853
Odawara
11 Mar 1853 · 200 km away
79 deathsSevere damage ($5–24M)
- 1894M7.5
Tokyo
20 Jun 1894 · 182 km away
24 deathsLimited damage (under $1M)
- 1782M7.3
Tokaido, Japan
22 Aug 1782 · 166 km away
Severe damage ($5–24M)tsunami
- 1857M6.4
Tokaido, Japan
13 Jul 1857 · 286 km away
Limited damage (under $1M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.