3.5

M3.5 Earthquake 178 km E of Atka, AlaskaMay 16, 2026

2026-05-16 07:21:10 UTC (4 days ago) · approx. 8:21 PM UTC-11 local

MagnitudeM3.5(ml)
Time07:21 UTC8:21 PM UTC-11
Depth27.3 kmshallow crustal
Coordinates52.054°, -171.600°
Felt byNo felt reports
Status✓ Reviewed by USGS

On May 16, 2026 at 07:21 UTC, a magnitude 3.5 shallow crustal earthquake struck 178 km E of Atka, Alaska, at a depth of 27.3 km and coordinates 52.0540°, -171.6000°.

Physical scale: An earthquake of magnitude 3.5 releases seismic energy equivalent to roughly 2.7 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 157 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 52.05°, -171.60°

ShakeMap — predicted shaking intensity

Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.

USGS ShakeMap intensity contours for the M3.5 earthquake near 178 km E of Atka, Alaska

Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS

Earthquake Details

Magnitude
3.5 ml
Depth
27.3 km
shallow crustal
Location
52.0540°N
-171.6000°E
Intensity (MMI)
1.9
weak

Technical Information

Event ID
aka2026jpxrss
Event Type
earthquake
Status
✓ Reviewed
Significance
188
Stations Used
20
Azimuthal Gap
216.0°
Min Station Distance
1.300°
RMS Residual
0.60 sec
Last Updated
2026-05-18 19:21:00 UTC

Common Questions

How strong was the magnitude 3.5 earthquake near Atka, Alaska?

The magnitude 3.5 earthquake that struck 178 km E of Atka, Alaska on May 16, 2026 at 07:21 UTC had a depth of 27.3 km. For context, this was a minor earthquake typically detected only by instruments.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 3.5 earthquakes can continue for several days and gradually diminish over time.

What should I do after an earthquake?

If you were in the affected area: check yourself and others for injuries, inspect your home for damage, and be prepared for aftershocks. For detailed guidance, see our earthquake safety guide and emergency planning resources.

Authoritative source: USGS event page (event ID: aka2026jpxrss). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2026, May 16, 2026). M3.5 Earthquake 178 km E of Atka, AlaskaMay 16, 2026. Retrieved May 20, 2026 from https://www.earthquaketracker.org/earthquakes/event/aka2026jpxrss/