M4.6 earthquake 111 km NW of Hihifo, Tonga
A magnitude 4.6 earthquake struck 111 km NW of Hihifo, Tonga on Tue, Apr 21, 1987, 12:50 PM GMT-11 (23:50 UTC), 33 km (21 mi) below the surface.
A larger quake followed: M5.7 74 km NNE of Hihifo, 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, body-wave), light
- Magnitude from
- USGS National Earthquake Information Center
- Local time
- UTC
- 1987-04-21 23:50:46 UTC
- Depth
- 33.0 km (20.5 mi), shallow
- Epicenter
- 15.120° S, 174.374° 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
Nearest places
Distance and direction from each place to the epicenter, with its forecast.
Nearby
Within 100 km, magnitude 1.6 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 usp00034br. Read Thu, Oct 1, 2026, 11:53 AM UTC.