Reviewed by USGSJapan104y ago
M6.5 earthquake 170 km ESE of Naze, Japan
Tuesday, November 6, 1923, 19:18:28 UTC · 28.065°N, 131.187°E
A magnitude 6.5 earthquake struck 170 km ESE of Naze, Japan on Tuesday, November 6, 1923, 19:18:28 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M7.2 on November 5, 1923.
- Magnitude
- 6.5
- 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
85 kilotons of TNT
That is about 6 times the Hiroshima bomb. It released about 178 times the energy of a magnitude 5.0.
Tectonic setting
29 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
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 15 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.9108 km NW of Naze, JapanJune 15, 1911 · 262 km NW of this epicenter
- 7.4152 km ESE of Koshima, JapanFebruary 1, 1916 · 174 km N of this epicenter
- 7.2Ryukyu Islands, JapanJune 24, 1901 · 117 km W of this epicenter
- 7.2101 km NE of Naze, JapanNovember 5, 1923 · 128 km NW of this epicenter
- 7.161 km ESE of Nishinoomote, JapanAugust 24, 1904 · 270 km N of this epicenter
- 7.093 km NNE of Naze, JapanNovember 3, 1923 · 167 km NW of this epicenter
- 6.786 km SE of Koshima, JapanNovember 28, 1914 · 171 km N of this epicenter
- 6.628 km S of Nishinoomote, JapanJuly 13, 1923 · 269 km N 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 12 recorded deaths. The most severe:
- 1911M8.0
Ryukyu Islands
15 Jun 1911 · 117 km away
12 deathsSevere damage ($5–24M)tsunami
- 1901M7.9
Ryukyu Islands
24 Jun 1901 · 166 km away
Limited damage (under $1M)tsunami
- 1916M8.0
Duda
1 Feb 1916 · 162 km away
- 1904M7.9
Kyushu
24 Aug 1904 · 244 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.