Moderate Earthquake ● Closed
M5.8 Earthquake — 99 km SE of Atka, Alaska
Loading live data… · Marker positions are approximate; severity is labelled in each popup. Sources: USGS, GDACS, NASA EONET, NOAA/NWS, EMSC.
Magnitude 5.8 earthquake 99 km SE of Atka, Alaska at a depth of 10.0 km, recorded by the U.S. Geological Survey.
Measurements
| Magnitude | M5.8 |
|---|---|
| Depth | 10.0 km |
| Coordinates | 51.4994, -173.3060 |
| Region | 99 km SE of Atka, Alaska |
| Usgs Alert | green |
| Tsunami Flag | 0 |
Measured by
Earthquake data courtesy of the U.S. Geological Survey
This is a scientific measurement of an event that has already happened. It is not a warning, and it does not tell you what to do.
Not rated by source. US Geological Survey does not publish a severity for this; the level shown is our own classification.
View original reportAlso reported by: EMSC GDACS
This event as JSON · API and licence
Source updated 84 days ago (Jul 27, 2026 02:45 UTC) · we last heard from US Geological Survey 47 seconds ago
On a slow connection? Low-bandwidth version — no map, no scripts, under 14 KB.
What USGS has published since this earthquake
Aftershock forecast
USGS gives less than a 1% chance of at least one aftershock of magnitude 5 or larger in the week to 25 Oct 2026, less than a 1% chance of magnitude 6 or larger, and less than a 1% chance of magnitude 7 or larger.
USGS puts less than a 1% chance on an earthquake larger than this magnitude 5.8 following in the week to 25 Oct 2026.
Since the mainshock USGS has recorded 11 aftershocks of magnitude 3 or larger.
| Chance of at least one aftershock in | M5+ | M6+ | M7+ |
|---|---|---|---|
| the week to 25 Oct 2026 | <1% | <1% | <1% |
| the month to 17 Nov 2026 | <1% | <1% | <1% |
| the year to 18 Oct 2027 | 4% | <1% | <1% |
USGS forecast issued 18 Oct 2026 08:35 UTC, generated automatically. A forecast gives chances, not times: it cannot say when or where an aftershock will strike.
Shaking and its likely impact
USGS estimates fewer than 1,000 people were exposed to strong shaking or worse (intensity VI and above).
USGS's PAGER system gives a green alert for deaths, meaning a low likelihood of casualties; and a green alert for economic losses, meaning a low likelihood of damage. These are estimates from a model of the shaking and the population it reached, not a count.
USGS PAGER, automatic.
How far the shaking reached
- Moderate shaking (intensity V) or more reached about 15 km from the epicentre at its farthest.
- Light shaking (intensity IV) or more reached about 50 km from the epicentre at its farthest.
USGS ShakeMap, automatic: an estimate built from seismic stations, felt reports and a model where there are neither. Distances are in a straight line from USGS's epicentre; the lines on the map above are USGS's contours, simplified. Shaking varies with the ground, so a place inside a line may have felt less or more.
From the U.S. Geological Survey. The USGS event page has the maps and everything USGS has published for this earthquake.
General safety information
No authority has issued instructions for this event. The guidance below is general background reading, not a response to it.
Drop, Cover, and Hold On — what to do before, during and after an earthquake, plus emergency kit and family plan checklists.
Open Earthquake Safety Guide →Nearby & related events
Disclaimer: figures are automatic feeds from the named agencies and may be revised. Do not use this page for life-safety decisions — follow official local emergency services.