4.1

M4.1 Earthquake south of the Fiji IslandsNovember 4, 2025

2025-11-04 20:40:51 UTC (2025-11-04) · approx. 8:40 AM UTC-12 local

MagnitudeM4.1(mb)
Time20:40 UTC8:40 AM UTC-12
Depth548.1 kmdeep-focus
Coordinates-23.404°, -179.957°
Felt byNo felt reports
Status✓ Reviewed by USGS

On November 4, 2025 at 20:40 UTC, a magnitude 4.1 deep-focus earthquake struck south of the Fiji Islands, at a depth of 548.1 km and coordinates -23.4037°, -179.9567°.

Physical scale: An earthquake of magnitude 4.1 releases seismic energy equivalent to roughly 21 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 406 m — a useful intuition for the size of the slip patch on the fault.

This earthquake is part of an ongoing aftershock sequence following the magnitude 5.0 mainshock that occurred 15 days ago south of the Fiji Islands. 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.

Map showing earthquake epicenter at -23.40°, -179.96°

Earthquake Details

Magnitude
4.1 mb
Depth
548.1 km
deep-focus
Location
-23.4037°N
-179.9567°E

Technical Information

Event ID
us7000rdi0
Event Type
earthquake
Status
✓ Reviewed
Significance
259
Stations Used
15
Azimuthal Gap
198.0°
Min Station Distance
5.931°
RMS Residual
0.37 sec
Last Updated
2026-01-27 17:59:12 UTC

Common Questions

How strong was the magnitude 4.1 earthquake south of the Fiji Islands?

The magnitude 4.1 earthquake that struck south of the Fiji Islands on November 4, 2025 at 20:40 UTC had a depth of 548.1 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 4.1 earthquakes can continue for several days and gradually diminish over time.

Is this the same earthquake as the M5.0 one earlier?

No. This magnitude 4.1 earthquake is an aftershock of the larger magnitude 5.0 mainshock that occurred earlier south of the Fiji Islands. Aftershocks are smaller earthquakes triggered by stress changes from the mainshock.

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: us7000rdi0). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2025, November 4, 2025). M4.1 Earthquake south of the Fiji IslandsNovember 4, 2025. Retrieved May 26, 2026 from https://www.earthquaketracker.org/earthquakes/event/us7000rdi0/