4.2

M4.2 Earthquake 192 km W of Neiafu, TongaApril 23, 2026

2026-04-23 14:38:05 UTC (2026-04-23) · approx. 2:38 AM UTC-12 local

MagnitudeM4.2(mb)
Time14:38 UTC2:38 AM UTC-12
Depth278.0 kmintermediate depth
Coordinates-18.614°, -175.811°
Felt byNo felt reports
Status✓ Reviewed by USGS

On April 23, 2026 at 14:38 UTC, a magnitude 4.2 intermediate depth earthquake struck 192 km W of Neiafu, Tonga, at a depth of 278.0 km and coordinates -18.6143°, -175.8107°.

Physical scale: An earthquake of magnitude 4.2 releases seismic energy equivalent to roughly 30 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 476 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at -18.61°, -175.81°

Earthquake Details

Magnitude
4.2 mb
Depth
278.0 km
intermediate depth
Location
-18.6143°N
-175.8107°E

Technical Information

Event ID
us7000sha6
Event Type
earthquake
Status
✓ Reviewed
Significance
271
Stations Used
22
Azimuthal Gap
167.0°
Min Station Distance
5.064°
RMS Residual
0.47 sec
Last Updated
2026-05-08 19:06:50 UTC

Common Questions

How strong was the magnitude 4.2 earthquake near Neiafu, Tonga?

The magnitude 4.2 earthquake that struck 192 km W of Neiafu, Tonga on April 23, 2026 at 14:38 UTC had a depth of 278.0 km. For context, this was a light earthquake commonly felt near the epicenter.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.2 earthquakes can continue for several days and gradually diminish over time.

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: us7000sha6). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2026, April 23, 2026). M4.2 Earthquake 192 km W of Neiafu, TongaApril 23, 2026. Retrieved May 19, 2026 from https://www.earthquaketracker.org/earthquakes/event/us7000sha6/