M4.9 earthquake 66 km ESE of ‘Ohonua, Tonga
A magnitude 4.9 earthquake struck 66 km ESE of ‘Ohonua, Tonga on Wed, Mar 19, 1975, 12:04 PM GMT+13 (23:04 UTC), 33 km (21 mi) below the surface.
A larger quake followed: M5.1 120 km SSE of Pangai, Tonga. This one was a foreshock.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 4.9 (ms), light
- Local time
- UTC
- 1975-03-18 23:04:32 UTC
- Depth
- 33.0 km (20.5 mi), shallow
- Epicenter
- 21.452° S, 174.324° 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.
- Depth from
- OPERATOR_ASSIGNED
- Stations used
- 9
Nearest places
Distance and direction from each place to the epicenter, with its forecast.
Nearby
Within 100 km, magnitude 1.9 and up: 4 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 usp0000aa0. Read Tue, Sep 29, 2026, 12:11 AM UTC.