M 5.5 Earthquake Strikes 100 km S of Nikolski, Alaska
Areazine synthesizes this USGS earthquake report directly from USGS's official public data feed. See our methodology for full source attribution and refresh cadence.
A magnitude 5.5 mww earthquake occurred 100 km south of Nikolski, Alaska, at a depth of 10 km.
What this USGS earthquake report tells you, and what most readers miss
This notice was issued by USGS on September 3, 2026 and geographically references Alaska. Its severity classification of "medium" signals how the issuing agency weighs the risk of harm if no action is taken - "critical" and "high" tier alerts typically carry direct consumer actions, while "medium" and "low" tend toward informational guidance or monitoring advisories. The category it belongs to - Earthquakes - determines the monitoring protocol behind it, which shapes what follow-up action (checking for structural damage, watching for aftershocks, reviewing local building codes) is relevant and which agency holds authority over the assessment.
Most readers skim a notice like this, check whether they are personally affected, and move on. The more useful lens is to verify its scope, source, and timestamp, then compare related notices without assuming that one record proves a broader trend.
Areazine pairs this record with the original agency URL so you can check the primary source before acting. Its related labels are earthquake, seismic, usgs, Alaska.
What Happened
A M 5.5 mww earthquake struck 100 km S of Nikolski, Alaska, at 2026-08-04 12:21:15 UTC. The event had a depth of 10 km.
Location Details
The epicenter was located at latitude 52.0506, longitude -169.1387. This places the event 100 km south of Nikolski, Alaska. A depth of 10 km is classified as shallow.
Impact Assessment
No felt reports are available in the data. The tsunami flag is 0, indicating no tsunami advisory. The maximum estimated shaking intensity (MMI) is 2.988. No alert level is assigned.
What You Should Know
This magnitude corresponds to a moderate earthquake that can cause damage to poorly constructed buildings. Aftershocks are possible following any earthquake.
Source
Original source: USGS Official Notice ↗
Related Earthquakes
All Earthquakes →Nationwide notices with similar length or severity timing 8
Two Areazine-derived peer sets for this USGS earthquake report: nearest notices by body length and by same severity near the same agency date. Peers come from other categories so they are not the same-feed Related list above.
Similar body length
Nearest notices by article body length (802 characters here).
Similar severity timing
Same severity (medium) notices issued closest in time to September 3, 2026.
Frequently Asked Questions
Common questions about this USGS earthquake report.