4.3

M4.3 Earthquake 157 km NW of Neiafu, TongaOctober 19, 2025

2025-10-19 18:50:05 UTC (2025-10-19) · approx. 6:50 AM UTC-12 local

MagnitudeM4.3(mb)
Time18:50 UTC6:50 AM UTC-12
Depth241.1 kmintermediate depth
Coordinates-17.551°, -174.923°
Felt byNo felt reports
Status✓ Reviewed by USGS

On October 19, 2025 at 18:50 UTC, a magnitude 4.3 intermediate depth earthquake struck 157 km NW of Neiafu, Tonga, at a depth of 241.1 km and coordinates -17.5506°, -174.9229°.

Physical scale: An earthquake of magnitude 4.3 releases seismic energy equivalent to roughly 43 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 558 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at -17.55°, -174.92°

Earthquake Details

Magnitude
4.3 mb
Depth
241.1 km
intermediate depth
Location
-17.5506°N
-174.9229°E

Technical Information

Event ID
us6000ri6t
Event Type
earthquake
Status
✓ Reviewed
Significance
284
Stations Used
25
Azimuthal Gap
119.0°
Min Station Distance
4.717°
RMS Residual
0.53 sec
Last Updated
2026-01-09 15:38:41 UTC

Common Questions

How strong was the magnitude 4.3 earthquake near Neiafu, Tonga?

The magnitude 4.3 earthquake that struck 157 km NW of Neiafu, Tonga on October 19, 2025 at 18:50 UTC had a depth of 241.1 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 4.3 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: us6000ri6t). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2025, October 19, 2025). M4.3 Earthquake 157 km NW of Neiafu, TongaOctober 19, 2025. Retrieved May 27, 2026 from https://www.earthquaketracker.org/earthquakes/event/us6000ri6t/