Moderate M 5.5 Earthquake Strikes 92 km SW of Nikolski, Alaska

What Happened

A moderate earthquake measuring magnitude 5.5 (mww) occurred on February 24, 2026, at 10:02:08 UTC. The seismic event was recorded at a shallow depth of 10 kilometers.

Location Details

The epicenter was located at coordinates 52.4087°N, 169.9056°W, approximately 92 kilometers southwest of Nikolski, Alaska. The 10 km depth is classified as shallow; shallow earthquakes (less than 20 km) typically result in more intense shaking at the surface compared to deeper events of the same magnitude.

Impact Assessment

The USGS has issued a green alert level for this event, indicating a low likelihood of casualties or significant economic damage. A tsunami advisory or information statement was issued in connection with this earthquake. At this time, no felt reports have been submitted to the USGS, and the Modified Mercalli Intensity (MMI) was recorded at 4.136.

What You Should Know

Moderate earthquakes of this magnitude (M 5.0-5.9) are capable of causing damage to poorly constructed buildings but usually result in light to no damage for well-built structures. Residents in the Aleutian Islands region should remain aware of the potential for aftershocks following this event.

Source

Data and attribution provided by the USGS Earthquake Hazards Program.