How strong was the 71 km SSW of Adak, Alaska earthquake?
The 71 km SSW of Adak, Alaska earthquake had a magnitude of 4.9 mwr, classified as a "Light" earthquake on the magnitude scale. Earthquakes of this magnitude are typically felt by people nearby but rarely cause significant structural damage.
Where exactly did this earthquake occur and how deep was it?
This earthquake struck at coordinates 51.2964N, 177.0718W, at a depth of 37.3 km. This intermediate depth can still produce significant shaking at the surface.
Did this earthquake trigger a tsunami warning?
No tsunami warning was issued for this earthquake. Earthquakes below magnitude 6.5 rarely generate dangerous tsunamis, though localized effects are possible in rare cases.
How many people felt this earthquake?
2 people submitted felt reports to the USGS for this earthquake. The Community Decimal Intensity (CDI) reached 2.5, indicating light shaking noticed by some people. The Modified Mercalli Intensity (MMI) was estimated at 3.3.
When did this earthquake happen and how significant was it?
This earthquake occurred on October 21, 2025 at 03:45:26. The USGS assigned it a significance score of 370 out of a possible 3,000, which factors in magnitude, felt reports, and potential impact. This is a relatively routine seismic event.