Magnitude 4.9 Light Earthquake Strikes Near Adak, Alaska
A magnitude 4.9 earthquake occurred 120 km west-southwest of Adak, Alaska, on February 18, 2026. The shallow quake did not trigger a tsunami advisory.
What Happened
A light earthquake with a magnitude of 4.9 ml occurred on Wednesday, February 18, 2026, at 23:12:50 UTC (approximately 1:12 PM local time in Adak). The event was centered approximately 120 km west-southwest of Adak, Alaska, at a shallow depth of 18.6 km.
Location Details
The seismic event was located at coordinates 51.288°N and 178.094°W. The recorded depth of 18.6 km is classified as shallow. Shallow earthquakes—those occurring at depths of less than 20 km—are typically felt more distinctly at the surface than deeper seismic events of the same magnitude.
Impact Assessment
According to the U.S. Geological Survey (USGS), there are currently no felt reports associated with this event. The Modified Mercalli Intensity (MMI) was calculated at 4.366, which corresponds to light shaking. Data indicates there is no tsunami advisory, watch, or warning in effect. No specific PAGER alert level (color) was issued for this event.
What You Should Know
A magnitude 4.9 earthquake is categorized as a “light” earthquake. While these events cause noticeable shaking and are frequently felt, they rarely result in significant structural damage. Residents in the Aleutian Islands region should be aware that aftershocks are a routine possibility following an event of this size. In the event of further shaking, safety officials recommend you “Drop, Cover, and Hold On.”
Source
Data and attribution provided by the USGS Earthquake Hazards Program.
Source: USGS Official Notice