4.9

M4.9 Earthquake south of the Fiji IslandsFebruary 17, 2026

2026-02-17 15:11:15 UTC (2026-02-17) · approx. 3:11 AM UTC+12 local

Aftershock of the M5.0 mainshock.

MagnitudeM4.9(mb)
Time15:11 UTC3:11 AM UTC+12
Depth543.2 kmdeep-focus
Coordinates-23.584°, 179.845°
Felt byNo felt reports
Status✓ Reviewed by USGS

On February 17, 2026 at 15:11 UTC, a magnitude 4.9 deep-focus earthquake struck south of the Fiji Islands, at a depth of 543.2 km and coordinates -23.5837°, 179.8445°. This earthquake was detected by 147 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 369, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 4.9 releases seismic energy equivalent to roughly 338 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 1.4 km — 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 9 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.

The epicenter is located in Fiji, a region characterized by the Fiji Fracture Zone at the junction of the Pacific and Australian plates, with deep-focus seismicity from the subducted slab. View all earthquakes in Fiji.

Learn more: Magnitude scale · Aftershock sequences

Map showing earthquake epicenter at -23.58°, 179.84°

Earthquake Details

Magnitude
4.9 mb
Depth
543.2 km
deep-focus
Location
-23.5837°N
179.8445°E

Technical Information

Event ID
us6000s9sa
Event Type
earthquake
Status
✓ Reviewed
Significance
369
Stations Used
147
Azimuthal Gap
35.0°
Min Station Distance
6.046°
RMS Residual
0.80 sec
Last Updated
2026-05-06 17:54:00 UTC

Common Questions

How strong was the magnitude 4.9 earthquake south of the Fiji Islands?

The magnitude 4.9 earthquake that struck south of the Fiji Islands on February 17, 2026 at 15:11 UTC had a depth of 543.2 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at -23.5837°, 179.8445°, which is south of the Fiji Islands. View all earthquakes in Fiji.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.9 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 4.9 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: us6000s9sa). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2026, February 17, 2026). M4.9 Earthquake south of the Fiji IslandsFebruary 17, 2026. Retrieved May 20, 2026 from https://www.earthquaketracker.org/earthquakes/event/us6000s9sa/