M5.9 earthquake 83 km SSE of ‘Ohonua, Tonga
A magnitude 5.9 earthquake struck 83 km SSE of ‘Ohonua, Tonga on Mon, Sep 6, 2021, 6:51 AM GMT+13 (17:51 UTC), 10 km (6 mi) below the surface.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 5.9 (mww), moderate
- Local time
- UTC
- 2021-09-05 17:51:44 UTC
- Depth
- 10.0 km (6.2 mi), shallow
- Epicenter
- 22.011° S, 174.592° W
- Region
- Tonga
- Felt reports
- 3
- Strongest shaking
- IV, light shaking
- PAGER alert
- Green
- Tsunami flag
- No
- Status
- Reviewed by a seismologist
Shaking
The USGS ShakeMap: shaking estimated from seismic stations and the quake’s size, on the Modified Mercalli intensity scale.
- Strongest estimated
- IV, light shaking
- Peak ground acceleration
- 2.2% of gravity
- Peak ground velocity
- 1.5 cm/s
- Map
- Automatic
Did you feel it?
3 people reported to the USGS what they felt; the strongest reported shaking was IV, light shaking.
Estimated impact
The USGS PAGER system estimates deaths and economic losses from the shaking and the population and buildings exposed to it.
- Alert level
- Green: little or no damage or loss of life expected
| Range | Chance |
|---|---|
| Under 1 | 65% |
| 1 to 10 | 30% |
| 10 to 100 | 4% |
| 100 to 1,000 | Under 1% |
| 1,000 to 10,000 | Under 1% |
| 10,000 to 100,000 | Under 1% |
| 100,000 to 10,000,000 | Under 1% |
| Range, million USD | Chance |
|---|---|
| Under 1 | 65% |
| 1 to 10 | 30% |
| 10 to 100 | 4% |
| 100 to 1,000 | Under 1% |
| 1,000 to 10,000 | Under 1% |
| 10,000 to 100,000 | Under 1% |
| 100,000 to 10,000,000 | Under 1% |
Fault motion and ground failure
How the rock slipped, from the moment tensor, and the USGS estimate of landslides and liquefaction.
- Faulting
- Reverse (thrust)
- Moment magnitude
- 5.9 Mww
- Nodal plane 1
- Strike 204°, dip 23°, rake 83°
- Nodal plane 2
- Strike 32°, dip 67°, rake 93°
How well it is located
Reviewed by a seismologist.
- Location uncertainty
- About 8.9 km horizontally, 1.7 km in depth
- Magnitude uncertainty
- ±0.07
- Depth from
- From modeling of broad-band P waveforms
- Station coverage gap
- 29°
- Stations used
- 109
Nearest places
Distance and direction from each place to the epicenter, with its forecast.
Nearby
Within 100 km, magnitude 2.9 and up: 8 in the 60 days after this one and 6 in the 30 days before it.
After
- 4.7171 km SSE of ‘Ohonua, Tonga · 1841 days ago · 10 km deep · 88 km away
- 4.280 km S of ‘Ohonua, Tonga · 1838 days ago · 35 km deep · 45 km away
- 4.893 km E of ‘Ohonua, Tonga · 1833 days ago · 10 km deep · 83 km away
- 4.3146 km SSE of ‘Ohonua, Tonga · 1826 days ago · 10 km deep · 64 km away
- 4.5139 km SSE of ‘Ohonua, Tonga · 1802 days ago · 10 km deep · 59 km away
- 4.5137 km SSE of ‘Ohonua, Tonga · 1796 days ago · 10 km deep · 54 km away
- 4.7148 km S of ‘Ohonua, Tonga · 1795 days ago · 10 km deep · 76 km away
- 4.8Tonga region · 1795 days ago · 10 km deep · 97 km away
Before
- 4.6157 km SSE of ‘Ohonua, Tonga · 1857 days ago · 10 km deep · 74 km away
- 4.8158 km SSE of ‘Ohonua, Tonga · 1865 days ago · 10 km deep · 75 km away
- 5.0113 km SSE of ‘Ohonua, Tonga · 1868 days ago · 10 km deep · 33 km away
- 4.5154 km SE of ‘Ohonua, Tonga · 1872 days ago · 10 km deep · 82 km away
- 5.6127 km SSE of ‘Ohonua, Tonga · 1874 days ago · 10 km deep · 46 km away
- 4.6157 km SSE of ‘Ohonua, Tonga · 1880 days ago · 10 km deep · 74 km away
Earthquakes todayTonga earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event us7000f8bb (also filed as usauto7000f8bb, pt21248001, at00qyz2y9, iscgem621240957). Read Wed, Sep 30, 2026, 11:44 PM UTC.