M4.2 Earthquake 69 km SSW of Severo-Kuril’sk, Russia — October 17, 2025
2025-10-17 19:27:10 UTC (2025-10-17) · approx. 5:27 AM UTC+10 local
On October 17, 2025 at 19:27 UTC, a magnitude 4.2 intermediate depth earthquake struck 69 km SSW of Severo-Kuril’sk, Russia, at a depth of 88.2 km and coordinates 50.0643°, 155.9152°.
Physical scale: An earthquake of magnitude 4.2 releases seismic energy equivalent to roughly 30 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 476 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 11 days ago 78 km S of Severo-Kuril’sk, Russia. Since the mainshock, the USGS has recorded 2 aftershocks in this area. Aftershock activity is expected to continue for days to weeks as stresses on surrounding faults redistribute.
Earthquake Details
155.9152°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 4.2 earthquake near Severo-Kuril’sk, Russia?
The magnitude 4.2 earthquake that struck 69 km SSW of Severo-Kuril’sk, Russia on October 17, 2025 at 19:27 UTC had a depth of 88.2 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 4.2 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 4.2 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.
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Understanding This Data
Magnitude 4.2 earthquakes are often felt but rarely cause damage.
Authoritative source: USGS event page (event ID: us6000rlyl). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2025, October 17, 2025). M4.2 Earthquake 69 km SSW of Severo-Kuril’sk, Russia — October 17, 2025. Retrieved January 9, 2026 from https://www.earthquaketracker.org/earthquakes/event/us6000rlyl/