4.0

M4.0 Earthquake 50 km S of Severo-Kuril’sk, RussiaAugust 17, 2025

2025-08-17 21:01:47 UTC (2025-08-17) · approx. 7:01 AM UTC+10 local

MagnitudeM4.0(mb)
Time21:01 UTC7:01 AM UTC+10
Depth64.5 kmshallow crustal
Coordinates50.218°, 156.136°
Felt byNo felt reports
Status✓ Reviewed by USGS

On August 17, 2025 at 21:01 UTC, a magnitude 4.0 shallow crustal earthquake struck 50 km S of Severo-Kuril’sk, Russia, at a depth of 64.5 km and coordinates 50.2185°, 156.1358°.

Physical scale: An earthquake of magnitude 4.0 releases seismic energy equivalent to roughly 15 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 347 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 5.3 mainshock that occurred 17 days ago 78 km S of Severo-Kuril’sk, 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 50.22°, 156.14°

Earthquake Details

Magnitude
4.0 mb
Depth
64.5 km
shallow crustal
Location
50.2185°N
156.1358°E

Technical Information

Event ID
us7000qvgc
Event Type
earthquake
Status
✓ Reviewed
Significance
246
Stations Used
41
Azimuthal Gap
154.0°
Min Station Distance
3.053°
RMS Residual
0.63 sec
Last Updated
2025-11-04 16:44:21 UTC

Common Questions

How strong was the magnitude 4.0 earthquake near Severo-Kuril’sk, Russia?

The magnitude 4.0 earthquake that struck 50 km S of Severo-Kuril’sk, Russia on August 17, 2025 at 21:01 UTC had a depth of 64.5 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 4.0 earthquakes can continue for several days and gradually diminish over time.

Is this the same earthquake as the M5.3 one earlier?

No. This magnitude 4.0 earthquake is an aftershock of the larger magnitude 5.3 mainshock that occurred earlier 78 km S of Severo-Kuril’sk, Russia. Aftershocks are smaller earthquakes triggered by stress changes from the mainshock.

Understanding This Data

Magnitude 4.0 earthquakes are often felt but rarely cause damage.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: us7000qvgc). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2025, August 17, 2025). M4.0 Earthquake 50 km S of Severo-Kuril’sk, RussiaAugust 17, 2025. Retrieved November 4, 2025 from https://www.earthquaketracker.org/earthquakes/event/us7000qvgc/