M7.7 earthquake 133 km NE of Hihifo, Tonga
A magnitude 7.7 earthquake struck 133 km NE of Hihifo, Tonga on Mon, Aug 31, 1981, 10:29 PM GMT-11 (09:29 UTC), 25 km (16 mi) below the surface.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 7.7 (ms), major
- Local time
- UTC
- 1981-09-01 09:29:31 UTC
- Depth
- 25.0 km (15.5 mi), shallow
- Epicenter
- 14.960° S, 173.085° W
- Region
- Tonga
- Strongest shaking
- V, moderate shaking
- Tsunami flag
- No
- Status
- Reviewed by a seismologist
Deaths and damage
From NOAA NCEI’s Significant Earthquake Database (record 4927), matched to this event by time and place.
- Deaths
- Few (about 1 to 50) with its tsunami and other effects
- Damage
- Limited (under about $1 million) with its tsunami and other effects
- Houses destroyed
- Few (about 1 to 50) with its tsunami and other effects
Where the literature gives no number, NCEI records a description on a scale of 1 to 4, printed here in its words. Damage is in millions of US dollars of the year of the event, not adjusted for inflation.
Shaking
The USGS ShakeMap: shaking estimated from seismic stations and the quake’s size, on the Modified Mercalli intensity scale.
- Strongest estimated
- V, moderate shaking
- Peak ground acceleration
- 6.7% of gravity
- Peak ground velocity
- 2.3 cm/s
- Map
- Automatic
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 4.7 and up: 19 in the 60 days after this one and 1 in the 30 days before it.
After
- 5.6105 km NNE of Hihifo, Tonga · 16459 days ago · 33 km deep · 29 km away
- 5.2113 km NNE of Hihifo, Tonga · 16459 days ago · 33 km deep · 30 km away
- 4.8112 km NNE of Hihifo, Tonga · 16459 days ago · 33 km deep · 26 km away
- 5.1111 km NE of Hihifo, Tonga · 16459 days ago · 33 km deep · 30 km away
- 5.788 km NE of Hihifo, Tonga · 16459 days ago · 33 km deep · 46 km away
- 5.6104 km NE of Hihifo, Tonga · 16458 days ago · 33 km deep · 31 km away
- 4.9115 km ENE of Hihifo, Tonga · 16458 days ago · 33 km deep · 56 km away
- 4.8136 km ENE of Hihifo, Tonga · 16458 days ago · 33 km deep · 85 km away
- 4.8127 km NE of Hihifo, Tonga · 16458 days ago · 33 km deep · 16 km away
- 5.5102 km ENE of Hihifo, Tonga · 16458 days ago · 33 km deep · 58 km away
- 5.3116 km N of Hihifo, Tonga · 16458 days ago · 33 km deep · 64 km away
- 4.7116 km NE of Hihifo, Tonga · 16457 days ago · 33 km deep · 41 km away
- 4.7154 km N of Hihifo, Tonga · 16456 days ago · 33 km deep · 79 km away
- 4.9104 km N of Hihifo, Tonga · 16449 days ago · 33 km deep · 58 km away
- 4.8110 km NE of Hihifo, Tonga · 16443 days ago · 33 km deep · 28 km away
- 4.737 km NE of Hihifo, Tonga · 16437 days ago · 123 km deep · 99 km away
- 4.772 km N of Hihifo, Tonga · 16421 days ago · 33 km deep · 76 km away
- 5.4102 km NE of Hihifo, Tonga · 16417 days ago · 33 km deep · 37 km away
- 4.9126 km ENE of Hihifo, Tonga · 16410 days ago · 48 km deep · 57 km away
Before
Earthquakes todayTonga earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event usp0001fkx (also filed as gcmtc090181b, gcmt19810901092932, atlas19810901092931, iscgem610759). Read Thu, Sep 24, 2026, 11:04 AM UTC.