Reviewed by USGSJapan115y ago
M6.6 earthquake 40 km ESE of Yonakuni, Japan
Tuesday, December 24, 1912, 18:07:26 UTC · 24.263°N, 123.335°E
A magnitude 6.6 earthquake struck 40 km ESE of Yonakuni, Japan on Tuesday, December 24, 1912, 18:07:26 UTC, at a depth of 35.0 km (shallow). It is the strongest earthquake within 300 km since an M6.8 on November 29, 1910.
- Magnitude
- 6.6
- Strong · mw
- Depth
- 35 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: 100 km aftershock search area
In context
How big was it, and why here?
Energy released
124 kilotons of TNT
That is about 8 times the Hiroshima bomb. It released about 260 times the energy of a magnitude 5.0.
Tectonic setting
67 km
from the nearest mapped plate boundary, between the Yangtze and Okinawa plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
35 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 lists 1 M2.5+ earthquake within 100 km in the following 30 days; the largest was M6.7 on January 7, 1913. 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 13 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 · 213 km NE of this epicenter
- 7.2108 km E of Hengchun, TaiwanJanuary 11, 1908 · 290 km SW of this epicenter
- 6.910 km NE of Pizitou, TaiwanMarch 16, 1906 · 298 km W of this epicenter
- 6.9136 km S of Hualien City, TaiwanNovember 14, 1910 · 228 km SW of this epicenter
- 6.813 km ENE of Hualien City, TaiwanNovember 21, 1909 · 165 km W of this epicenter
- 6.8TaiwanSeptember 1, 1910 · 186 km NW of this epicenter
- 6.859 km NE of Hirara, JapanNovember 29, 1910 · 259 km NE of this epicenter
- 6.73 km WSW of Banqiao, TaiwanApril 14, 1909 · 209 km NW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 18 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 57,240 recorded deaths. The most severe:
- 1782
Tainan
22 May 1782 · 288 km away
40,000 deathsSevere damage ($5–24M)tsunami
- 1771M7.4
Ryukyu Islands
24 Apr 1771 · 102 km away
13,486 deathsExtreme damage ($25M+)tsunami
- 1906M6.8
Jiayi
16 Mar 1906 · 297 km away
1,258 deathsSevere damage ($5–24M)
- 1848M6.8
Zhanghua
3 Dec 1848 · 288 km away · intensity IX
1,001 deathsExtreme damage ($25M+)
- 1867M7.0
Chilung (Keelung)
18 Dec 1867 · 187 km away
580 deathsModerate damage ($1–5M)tsunami
- 1845M6.0
Zhanghua
Feb 1845 · 288 km away · intensity VIII
380 deathsSevere damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.