M5.8 earthquake 223 km WNW of Pangai, Tonga
A magnitude 5.8 earthquake struck 223 km WNW of Pangai, Tonga on Thu, Sep 9, 2021, 5:59 PM GMT+13 (04:59 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
- 5.8 (mww), moderate
- Local time
- UTC
- 2021-09-09 04:59:43 UTC
- Depth
- 10.0 km (6.2 mi), shallow
- Epicenter
- 19.238° S, 176.396° W
- Region
- Tonga
- Felt reports
- 1
- 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
- 0.8% of gravity
- Peak ground velocity
- 0.8 cm/s
- Map
- Automatic
Did you feel it?
1 person reported to the USGS what they felt; the strongest reported shaking was II, weak 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
- Strike-slip
- Moment magnitude
- 5.8 Mww
- Nodal plane 1
- Strike 25°, dip 68°, rake 3°
- Nodal plane 2
- Strike 294°, dip 87°, rake 158°
How well it is located
Reviewed by a seismologist.
- Location uncertainty
- About 9.7 km horizontally, 1.8 km in depth
- Magnitude uncertainty
- ±0.06
- Depth from
- Operator assigned
- Station coverage gap
- 35°
- Stations used
- 82
Nearest places
Distance and direction from each place to the epicenter, with its forecast.
Nearby
Within 100 km, magnitude 2.8 and up: 3 in the 60 days after this one and 4 in the 30 days before it.
After
- 4.4291 km NW of Nuku‘alofa, Tonga · 1829 days ago · 574 km deep · 89 km away
- 4.6156 km NW of Nuku‘alofa, Tonga · 1828 days ago · 10 km deep · 97 km away
- 4.0Fiji region · 1788 days ago · 568 km deep · 98 km away
Before
Earthquakes todayTonga earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event us7000f9l5 (also filed as usauto7000f9l5, iscgem621240969). Read Tue, Sep 29, 2026, 7:02 PM UTC.