3.5

M3.5 Earthquake 15 km WNW of Atka, AlaskaAugust 3, 2026

2026-08-03 04:32:31 UTC (14 hours ago) · approx. 4:32 PM UTC-12 local

MagnitudeM3.5(ml)
Time04:32 UTC4:32 PM UTC-12
Depth174.5 kmintermediate depth
Coordinates52.269°, -174.397°
Felt byNo felt reports
Status✓ Reviewed by USGS

On August 3, 2026 at 04:32 UTC, a magnitude 3.5 intermediate depth earthquake struck 15 km WNW of Atka, Alaska, at a depth of 174.5 km and coordinates 52.2690°, -174.3970°.

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 52.27°, -174.40°

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 15 km WNW of Atka, Alaska

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

Earthquake Details

Magnitude
3.5 ml
Depth
174.5 km
intermediate depth
Location
52.2690°N
-174.3970°E
Intensity (MMI)
1.0
weak

Technical Information

Event ID
aka2026pfptyn
Event Type
earthquake
Status
✓ Reviewed
Significance
188
Stations Used
39
Azimuthal Gap
134.0°
Min Station Distance
0.100°
RMS Residual
0.50 sec
Last Updated
2026-08-03 18:23:00 UTC

Common Questions

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

The magnitude 3.5 earthquake that struck 15 km WNW of Atka, Alaska on August 3, 2026 at 04:32 UTC had a depth of 174.5 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.

Understanding This Data

Magnitude 3.5 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: aka2026pfptyn). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2026, August 3, 2026). M3.5 Earthquake 15 km WNW of Atka, AlaskaAugust 3, 2026. Retrieved August 3, 2026 from https://www.earthquaketracker.org/earthquakes/event/aka2026pfptyn/