4.8

M4.8 Earthquake 82 km NE of Hihifo, TongaMarch 28, 2026

2026-03-28 10:16:55 UTC (2026-03-28) · approx. 10:16 PM UTC-12 local

MagnitudeM4.8(mb)
Time10:16 UTC10:16 PM UTC-12
Depth10.0 kmshallow crustal
Coordinates-15.388°, -173.296°
Felt byNo felt reports
Status✓ Reviewed by USGS

On March 28, 2026 at 10:16 UTC, a magnitude 4.8 shallow crustal earthquake struck 82 km NE of Hihifo, Tonga, at a depth of 10.0 km and coordinates -15.3880°, -173.2957°. This earthquake was detected by 38 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 354, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 4.8 releases seismic energy equivalent to roughly 239 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 1.2 km — a useful intuition for the size of the slip patch on the fault.

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

Map showing earthquake epicenter at -15.39°, -173.30°

Earthquake Details

Magnitude
4.8 mb
Depth
10.0 km
shallow crustal
Location
-15.3880°N
-173.2957°E

Technical Information

Event ID
us7000s8cm
Event Type
earthquake
Status
✓ Reviewed
Significance
354
Stations Used
38
Azimuthal Gap
83.0°
Min Station Distance
2.076°
RMS Residual
0.52 sec
Last Updated
2026-05-08 12:07:41 UTC

Common Questions

How strong was the magnitude 4.8 earthquake near Hihifo, Tonga?

The magnitude 4.8 earthquake that struck 82 km NE of Hihifo, Tonga on March 28, 2026 at 10:16 UTC had a depth of 10.0 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at -15.3880°, -173.2957°, which is 82 km NE of Hihifo, Tonga. View all earthquakes in Tonga.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.8 earthquakes can continue for several days and gradually diminish over time.

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 4.8 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.

Authoritative source: USGS event page (event ID: us7000s8cm). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2026, March 28, 2026). M4.8 Earthquake 82 km NE of Hihifo, TongaMarch 28, 2026. Retrieved May 14, 2026 from https://www.earthquaketracker.org/earthquakes/event/us7000s8cm/