M5.8 Earthquake 286 km E of Poronaysk, Russia — September 3, 2021
2021-09-03 10:14:26 UTC (2021-09-03) · approx. 8:14 PM UTC+10 local
Felt by 4 people across nearby locations.
On September 3, 2021 at 10:14 UTC, a magnitude 5.8 deep-focus earthquake struck 286 km E of Poronaysk, Russia, at a depth of 585.0 km and coordinates 49.4861°, 147.0217°. The earthquake was reported felt by 4 peopleacross nearby locations, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 2.6 (weak). The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected.
Physical scale: An earthquake of magnitude 5.8 releases seismic energy equivalent to roughly 8 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 6.1 km — a useful intuition for the size of the slip patch on the fault.
The epicenter is located in Russia, a region characterized by the Kuril-Kamchatka subduction zone on the northwestern Pacific Ring of Fire. The nearest mapped fault system is the Kuril-Kamchatka Trench. View all earthquakes in Russia.
Learn more: Magnitude scale · Aftershock sequences
ShakeMap — predicted shaking intensity
Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.
Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS
Did You Feel It? — community-reported shaking
Aggregated felt-report intensity from 4 citizen responses to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.
Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report
Population exposure (USGS PAGER)
Estimated population that experienced each level of shaking. Based on the USGS PAGER rapid impact assessment, which combines ShakeMap output with global population grids.
| Shaking intensity (MMI) | Description | Population exposed |
|---|---|---|
| MMI 3 | weak | 19 |
Earthquake Details
147.0217°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 5.8 earthquake near Poronaysk, Russia?
The magnitude 5.8 earthquake that struck 286 km E of Poronaysk, Russia on September 3, 2021 at 10:14 UTC had a depth of 585.0 km. It was felt by 4 people with maximum shaking intensity of MMI 2.6 (weak). For context, this was a moderate earthquake that could be widely felt.
Where did the earthquake occur?
The earthquake epicenter was located at 49.4861°, 147.0217°, which is 286 km E of Poronaysk, Russia. View all earthquakes in Russia.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.8 earthquakes can continue for days to weeks and gradually diminish over time.
Has Russia had earthquakes this big before?
The largest recorded earthquake in Russia was the M9.0 Kamchatka earthquake of November 4, 1952. Today's magnitude 5.8 event is significantly smaller than that historical record.
Authoritative source: USGS event page (event ID: us7000f7en). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2021, September 3, 2021). M5.8 Earthquake 286 km E of Poronaysk, Russia — September 3, 2021. Retrieved December 22, 2025 from https://www.earthquaketracker.org/earthquakes/event/us7000f7en/