5.4-Magnitude Quake Jolts Aleutians West Coast

Lead A magnitude 5.4 earthquake struck the Bering Sea near Chuginadak Island in Alaska’s Aleutians West Census Area at 11:40 a.m. local time on Saturday, sending tremors through remote coastal communities and triggering tsunami advisories.

Nut Graf The temblor, the largest of five quakes registering 5.0 or greater worldwide on Sept. 6, underscores the Aleutian arc’s persistent seismic activity and prompted monitoring by the National Tsunami Warning Center to assess potential impacts on sparsely populated shorelines.

Key Facts

  • Magnitude & Location: 5.4, 36 mi south of Chuginadak Island, Alaska
  • Time: Saturday, Sept. 6, 2025, at 11:40 a.m. (GMT -9)
  • Global Context: Fifth day in a row of moderate seismic unrest, with five quakes ≥ 5.0 and 43 quakes ≥ 4.0 in the past 24 hours
  • Tsunami Advisory: Issued and later canceled after confirming wave heights below advisory thresholds

Seismic Overview

The Aleutian Islands arc, a boundary between the Pacific and North American tectonic plates, regularly experiences earthquakes due to subduction processes. While this offshore quake was too deep and distant to cause major damage, residents felt light shaking on Umnak and Adak islands. No injuries or structural damage have been reported.

Monitoring and Response

The National Tsunami Warning Center dispatched alerts to local authorities and coastal communities within the advisory zone. Mariners were advised to avoid close approach to affected shorelines until all wave activity subsided. Experts continue to analyze aftershocks-43 tremors of magnitude 4.0 or greater occurred globally on Saturday, highlighting elevated seismic energy release.

Community Preparedness

Local emergency management agencies reiterated that residents of the Aleutians follow established earthquake-response protocols: move to higher ground if coastal shaking is felt, secure heavy items indoors, and keep emergency kits accessible. Schools and municipal offices conducted rapid-drill evacuations to reinforce readiness for potential tsunami threats.

Subheadings Guide

  • Lead
  • Nut Graf
  • Key Facts
  • Seismic Overview
  • Monitoring and Response
  • Community Preparedness

Bullet Points

  • Concise event details (magnitude, location, time)
  • Contextual global seismic activity
  • Advisory actions and community drills