M4.6 earthquake Tonga
A magnitude 4.6 earthquake struck in Tonga on Sun, Mar 22, 1981, 7:36 AM GMT+13 (18:36 UTC), 72 km (45 mi) below the surface.
A larger quake followed: M5.7 76 km ESE of ‘Ohonua, Tonga. This one was a foreshock.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 4.6 (mb), light
- Local time
- UTC
- 1981-03-21 18:36:58 UTC
- Depth
- 72.0 km (44.7 mi), intermediate-depth
- Epicenter
- 21.279° S, 174.372° 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
- FROM_LOCATION
Nearest places
Distance and direction from each place to the epicenter, with its forecast.
Nearby
Within 100 km, magnitude 1.6 and up: 2 in the 60 days after this one and 1 in the 30 days before it.
After
- 5.776 km ESE of ‘Ohonua, Tonga · 16618 days ago · 43 km deep · 36 km away
- 5.189 km S of Pangai, Tonga · 16611 days ago · 33 km deep · 76 km away
Before
Earthquakes todayTonga earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event usp0001ctg. Read Thu, Sep 24, 2026, 7:00 AM UTC.