Reviewed by USGSJapan118y ago
M5.8 earthquake 12 km W of Ichihara, Japan
Friday, July 2, 1909, 20:54:25 UTC · 35.507°N, 139.948°E
A magnitude 5.8 earthquake struck 12 km W of Ichihara, Japan on Friday, July 2, 1909, 20:54:25 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M7.1 on March 13, 1909.
- Magnitude
- 5.8
- Moderate · 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
7 kilotons of TNT
That is about 1/2 of the Hiroshima bomb. It released about 14 times the energy of a magnitude 5.0.
Tectonic setting
83 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 75 km
USGS has not published any M2.5+ earthquake within 75 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 10 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.450 km SSW of Ōyama, JapanJanuary 21, 1906 · 230 km SW of this epicenter
- 7.3190 km SE of Hasaki, JapanSeptember 7, 1906 · 251 km E of this epicenter
- 7.238 km SSW of Shimoda, JapanOctober 24, 1905 · 164 km SW of this epicenter
- 7.1150 km ESE of Hasaki, JapanMarch 13, 1909 · 223 km E of this epicenter
- 7.082 km ENE of Hasaki, JapanMarch 12, 1909 · 166 km E of this epicenter
- 6.870 km E of Namie, JapanJanuary 15, 1908 · 283 km NE of this epicenter
- 6.6132 km ESE of Iwaki, JapanApril 8, 1906 · 252 km NE of this epicenter
- 6.473 km S of Shimoda, JapanSeptember 17, 1906 · 194 km SW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 26 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 38,187 recorded deaths. The most severe:
- 1847M7.4
Zenkoji, Nagano
8 May 1847 · 241 km away
12,000 deathsExtreme damage ($25M+)
- 1891M8.4
Mino-Owari
27 Oct 1891 · 267 km away
7,273 deathsExtreme damage ($25M+)
- 1855M7.0
Tokyo
11 Nov 1855 · 21 km away
6,757 deathsExtreme damage ($25M+)tsunami
- 1703M8.2
Off Sw Boso Peninsula
30 Dec 1703 · 57 km away
5,233 deathsExtreme damage ($25M+)tsunami
- 1751M6.6
Honshu: Nw
20 May 1751 · 251 km away
2,100 deathsExtreme damage ($25M+)tsunami
- 1707M8.4
Enshunada
28 Oct 1707 · 251 km away
2,000 deathsSevere damage ($5–24M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.