M5.5 earthquake 74 km SSE of ‘Ohonua, Tonga
A magnitude 5.5 earthquake struck 74 km SSE of ‘Ohonua, Tonga on Sun, Mar 6, 1966, 11:49 AM GMT+13 (22:49 UTC), 31 km (20 mi) below the surface.
A larger quake followed: M5.6 Tonga. This one was a foreshock.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 5.5 (mw), moderate
- Local time
- UTC
- 1966-03-05 22:49:35 UTC
- Depth
- 31.4 km (19.5 mi), shallow
- Epicenter
- 22.001° S, 174.802° W
- Region
- Tonga
- Tsunami flag
- No
- Status
- Reviewed by a seismologist
Did you feel it?
No one has reported feeling this quake to the USGS.
How well it is located
Reviewed by a seismologist.
- Magnitude uncertainty
- ±0.51
- Depth from
- From location
Nearest places
Distance and direction from each place to the epicenter, with its forecast.
Nearby
Within 100 km, magnitude 2.5 and up: 1 in the 60 days after this one and 0 in the 30 days before it.
After
Earthquakes todayTonga earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event iscgem848976. Read Tue, Sep 22, 2026, 3:13 AM UTC.