M5.7 Earthquake 106 km ENE of Hihifo, Tonga — March 23, 2026
2026-03-23 06:02:46 UTC (2026-03-23)
Aftershock of the M5.9 mainshock.
On March 23, 2026 at 06:02 UTC, a magnitude 5.7 shallow crustal earthquake struck 106 km ENE of Hihifo, Tonga, at a depth of 10.0 km and coordinates -15.5458°, -172.8966°. The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected. This earthquake was detected by 128 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 500, placing it among routine seismic activity. The nearest populated place is Nofoali`i (population 2,018).
This earthquake is part of an ongoing aftershock sequence following the magnitude 5.9 mainshock that occurred 27 days ago 110 km ENE of Hihifo, Tonga. Since the mainshock, the USGS has recorded 1 aftershocks in this area. Aftershock activity is expected to continue for days to weeks as stresses on surrounding faults redistribute.
The epicenter is located in Tonga, a region characterized by the Tonga-Kermadec subduction zone, where the Pacific Plate descends at up to 240 mm per year — the fastest plate convergence on Earth. The nearest mapped fault system is the Tonga Trench. View all earthquakes in Tonga.
Learn more: Magnitude scale · Aftershock sequences
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Earthquake Details
-172.8966°E
Technical Information
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Common Questions
How strong was the magnitude 5.7 earthquake near Hihifo, Tonga?
The magnitude 5.7 earthquake that struck 106 km ENE of Hihifo, Tonga on March 23, 2026 at 06:02 UTC had a depth of 10.0 km. For context, this was a moderate earthquake that could be widely felt.
Where did the earthquake occur?
The earthquake epicenter was located at -15.5458°, -172.8966°, which is 106 km ENE of Hihifo, Tonga. The nearest populated place is Nofoali`i (population 2,018). View all earthquakes in Tonga.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.7 earthquakes can continue for days to weeks and gradually diminish over time.
Is this the same earthquake as the M5.9 one earlier?
No. This magnitude 5.7 earthquake is an aftershock of the larger magnitude 5.9 mainshock that occurred earlier 110 km ENE of Hihifo, Tonga. Aftershocks are smaller earthquakes triggered by stress changes from the mainshock.
Has Tonga had earthquakes this big before?
The largest recorded earthquake in Tonga was the M8.1 Tonga Trench earthquake of June 26, 1917. Today's magnitude 5.7 event is significantly smaller than that historical record.
What should I do after an earthquake?
If you were in the affected area: check yourself and others for injuries, inspect your home for damage, and be prepared for aftershocks. For detailed guidance, see our earthquake safety guide and emergency planning resources.