Tonga earthquakes

M5.1 earthquake 126 km NE of Hihifo, Tonga

A magnitude 5.1 earthquake struck 126 km NE of Hihifo, Tonga on Tue, Aug 21, 2018, 7:24 PM GMT+13 (06:24 UTC), 10 km (6 mi) below the surface.

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Map

Where this earthquake was located, with the others nearby. Select one for its page.

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The earthquake

Magnitude: 5.1 (mb, body-wave), moderate
Magnitude from: USGS National Earthquake Information Center
Local time: Tue, Aug 21, 2018, 7:24 PM GMT+13
UTC: 2018-08-21 06:24:16 UTC
Depth: 10.0 km (6.2 mi), shallow
Epicenter: 15.058° S, 173.067° W
Region: Tonga
Tsunami flag: No
Status: Reviewed by a seismologist

Magnitude estimates

Different scales measure different things and differ by a few tenths. The USGS marks one as preferred, and it is the one this page uses.

Mag.	Scale	Computed by	Notes
5.1	mb, body-wave	USGS National Earthquake Information Center	Preferred · Reviewed · ±0.029 · 400 stations
5.01	Mw, moment	ISC-GEM global catalog	Final · ±0.1

Did you feel it?

No one has reported feeling this quake to the USGS.

How well it is located

Reviewed by a seismologist.

Location uncertainty: About 4.0 km horizontally, 1.8 km in depth
Magnitude uncertainty: ±0.03
Depth from: Operator assigned
Station coverage gap: 60°
Stations used: 93

Nearest places

Distance and direction from each place to the epicenter, with its forecast.

Apia, SamoaPopulation 40,407. Forecast195 kmSW

Nearby

Within 100 km, magnitude 2.1 and up: 7 in the 60 days after this one and 4 in the 30 days before it.

After

Before

Earthquakes today Tonga earthquakes Live radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event us1000gef4 (also filed as iscgem612548703). Read Sat, Oct 3, 2026, 12:17 AM UTC.