Reviewed by USGSJapan110y ago
M6.0 earthquake 122 km E of Hirara, Japan
Sunday, August 5, 1917, 18:38:23 UTC · 24.773°N, 126.514°E
A magnitude 6.0 earthquake struck 122 km E of Hirara, Japan on Sunday, August 5, 1917, 18:38:23 UTC, at a depth of 25.0 km (shallow). It is the strongest earthquake within 300 km since an M6.8 on July 4, 1917.
- Magnitude
- 6.0
- 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 earthquake
In context
How big was it, and why here?
Energy released
14 kilotons of TNT
That is about the energy of the Hiroshima bomb. It released about 29 times the energy of a magnitude 5.0.
Tectonic setting
82 km
from the nearest mapped plate boundary, between the Okinawa and Philippine Sea 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 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 8 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.11910 Taiwan EarthquakeApril 12, 1910 · 259 km NW of this epicenter
- 7.3120 km ENE of Hirara, JapanJuly 4, 1917 · 43 km N of this epicenter
- 7.012 km SE of Ginowan, JapanFebruary 23, 1911 · 207 km NE of this epicenter
- 6.892 km NNE of Hirara, JapanJuly 4, 1917 · 125 km NW of this epicenter
- 6.859 km NE of Hirara, JapanNovember 29, 1910 · 97 km NW of this epicenter
- 6.588 km NW of Hirara, JapanMay 2, 1906 · 196 km W of this epicenter
- 6.421 km SSW of Hirara, JapanMarch 25, 1916 · 129 km W of this epicenter
- 6.219 km SE of Ginowan, JapanAugust 29, 1909 · 205 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 4 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 13,486 recorded deaths. The most severe:
- 1771M7.4
Ryukyu Islands
24 Apr 1771 · 240 km away
13,486 deathsExtreme damage ($25M+)tsunami
- 1768M6.5
Ryukyu Islands
22 Jul 1768 · 187 km away
Limited damage (under $1M)tsunami
- 1853
Okinawa
3 Oct 1853 · 193 km away
tsunami
- 1858
Ryukyu Islands
Sep 1858 · 187 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.