4.3

M4.3 Earthquake 176 km SSE of Vilyuchinsk, RussiaSeptember 18, 2025

2025-09-18 22:32:12 UTC (2025-09-18) · approx. 9:32 AM UTC+11 local

MagnitudeM4.3(mb)
Time22:32 UTC9:32 AM UTC+11
Depth35.0 kmshallow crustal
Coordinates51.469°, 159.424°
Felt byNo felt reports
Status✓ Reviewed by USGS

On September 18, 2025 at 22:32 UTC, a magnitude 4.3 shallow crustal earthquake struck 176 km SSE of Vilyuchinsk, Russia, at a depth of 35.0 km and coordinates 51.4693°, 159.4240°.

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.

This earthquake is part of an ongoing aftershock sequence following the magnitude 5.1 mainshock that occurred 2 days ago 190 km SSE of Vilyuchinsk, Russia. 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 51.47°, 159.42°

Earthquake Details

Magnitude
4.3 mb
Depth
35.0 km
shallow crustal
Location
51.4693°N
159.4240°E

Technical Information

Event ID
us6000rg8h
Event Type
earthquake
Status
✓ Reviewed
Significance
284
Stations Used
22
Azimuthal Gap
169.0°
Min Station Distance
1.628°
RMS Residual
0.67 sec
Last Updated
2025-12-06 16:00:11 UTC

Common Questions

How strong was the magnitude 4.3 earthquake near Vilyuchinsk, Russia?

The magnitude 4.3 earthquake that struck 176 km SSE of Vilyuchinsk, Russia on September 18, 2025 at 22:32 UTC had a depth of 35.0 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 4.3 earthquakes can continue for several days and gradually diminish over time.

Is this the same earthquake as the M5.1 one earlier?

No. This magnitude 4.3 earthquake is an aftershock of the larger magnitude 5.1 mainshock that occurred earlier 190 km SSE of Vilyuchinsk, Russia. Aftershocks are smaller earthquakes triggered by stress changes from the mainshock.

Understanding This Data

Magnitude 4.3 earthquakes are often felt but rarely cause damage.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: us6000rg8h). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2025, September 18, 2025). M4.3 Earthquake 176 km SSE of Vilyuchinsk, RussiaSeptember 18, 2025. Retrieved December 6, 2025 from https://www.earthquaketracker.org/earthquakes/event/us6000rg8h/