Reviewed by USGSTonga121y ago
M7.2 earthquake 108 km SE of Neiafu, Tonga
Wednesday, December 19, 1906, 01:14:38 UTC · 19.229°S, 173.156°W
A magnitude 7.2 earthquake struck 108 km SE of Neiafu, Tonga on Wednesday, December 19, 1906, 01:14:38 UTC, at a depth of 35.0 km (shallow). It is the strongest earthquake within 300 km since an M8.0 on January 4, 1903.
- Magnitude
- 7.2
- Major · 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: 200 km aftershock search area
In context
How big was it, and why here?
Energy released
1.1 megatons of TNT
That is about 70 times the Hiroshima bomb. It released about 2,213 times the energy of a magnitude 5.0.
Tectonic setting
25 km
from the nearest mapped plate boundary, between the Tonga and Pacific 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 200 km
USGS lists 1 M2.5+ earthquake within 200 km in the following 30 days; the largest was M7.3 on January 2, 1907. 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 4 M5.0+ earthquakes 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 3 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1865M8.0
Tonga Islands
18 Nov 1865 · 47 km away
Limited damage (under $1M)tsunami
- 1903M8.0
Tonga Islands
4 Jan 1903 · 211 km away
- 1902M7.8
Tonga Islands
9 Feb 1902 · 123 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.