M 4.3 Earthquake 115 km WSW of Adak, 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 4.3 mb earthquake occurred 115 km west-southwest of Adak, Alaska, at an intermediate depth of 55 km.
What this USGS earthquake report tells you, and what most readers miss
This notice was issued by USGS on August 5, 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 4.3 mb earthquake struck 115 km WSW of Adak, Alaska, on July 9, 2026, at 12:01:55 UTC. The event was recorded at coordinates 51.4182°N, 178.1353°W with a depth of 55.234 km. This depth classifies as intermediate (20-70 km).
Location Details
The earthquake was centered 115 km west-southwest of Adak, Alaska, in the Aleutian region. Coordinates are latitude 51.4182, longitude -178.1353. The intermediate depth places the event below the Earth's crust but above deeper subduction zone activity.
Impact Assessment
No felt reports were recorded. The Modified Mercalli Intensity was measured at 3.49. There was no tsunami advisory (tsunami field = 0) and no alert level issued.
What You Should Know
This was a light earthquake (M 4.0-4.9 range), which can produce noticeable shaking but rarely causes significant damage. Residents in the region should follow standard earthquake preparedness practices.
Source
USGS Event Page - Data from USGS
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 (1,047 characters here).
Similar severity timing
Same severity (medium) notices issued closest in time to August 5, 2026.
Frequently Asked Questions
Common questions about this USGS earthquake report.