M 4.0 Earthquake 133 km E of Chalkyitsik, 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 4.0 mb earthquake struck 133 km east of Chalkyitsik, Alaska, at a depth of 11.4 km.
What this USGS earthquake report tells you, and what most readers miss
This notice was issued by USGS on August 1, 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 magnitude 4.0 mb earthquake occurred at 133 km E of Chalkyitsik, Alaska, on June 25, 2026, at 12:18 UTC. The event was recorded at a depth of 11.378 km and was classified as a light earthquake.
Location Details
The epicenter was located at latitude 66.64, longitude -140.7134. This places the event 133 km east of Chalkyitsik, Alaska. The depth of 11.378 km is considered shallow (less than 20 km).
Impact Assessment
No felt reports were recorded. The Modified Mercalli Intensity was measured at 4.101. There was no tsunami advisory (tsunami flag: 0) and no alert level issued.
What You Should Know
Earthquakes of this magnitude are often felt but rarely cause damage. Residents in the region should be prepared for possible aftershocks.
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 (859 characters here).
Similar severity timing
Same severity (medium) notices issued closest in time to August 1, 2026.
Frequently Asked Questions
Common questions about this USGS earthquake report.