Update: Earthquake measuring 5.5 hits area near Nikolski, AK on Feb. 23

Published Mar 17, 2026

ALEUTIANS WEST CENSUS AREA, AK — the U.S. Geological Survey reported a 5.5 magnitude quake struck close to Nikolski on Monday night.

At 10:02 a.m. (11:02 p.m. local time), a tremor shook the region at a depth of 5 miles, with its epicenter approximately 58 miles southwest of Nikolski. Seismologists first reported it as a 5.9 event, but later downgraded it to 5.5.

Did you feel it?

If you noticed the earthquake, you can report it through the USGS Felt Report form.

Impact and estimated losses

The USGS categorized this as a Green Alert, which means there is a low likelihood of casualties and damage.

Structure information summary
Most structures in this region are resistant to earthquake shaking, though vulnerable structures exist. The predominant vulnerable building types are unreinforced brick masonry and reinforced masonry construction.

Tremors last week

Over the last week, there have been eight tremors with a magnitude 2.5 or greater centered nearby. The largest one was a 6.1 earthquake that rocked the same region prior to this quake.

Source: The U.S. Geological Survey