3.1

M3.1 Earthquake 97 km S of Akhiok, AlaskaAugust 28, 2026

2026-08-28 10:18:23 UTC (9 hours ago) · approx. 12:18 AM UTC-10 local

MagnitudeM3.1(ml)
Time10:18 UTC12:18 AM UTC-10
Depth24.0 kmshallow crustal
Coordinates56.079°, -154.419°
Felt byNo felt reports
Status✓ Reviewed by USGS

On August 28, 2026 at 10:18 UTC, a magnitude 3.1 shallow crustal earthquake struck 97 km S of Akhiok, Alaska, at a depth of 24.0 km and coordinates 56.0790°, -154.4190°.

Physical scale: An earthquake of magnitude 3.1 releases seismic energy equivalent to roughly 674 kg of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 83 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 56.08°, -154.42°

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 M3.1 earthquake near 97 km S of Akhiok, Alaska

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

Earthquake Details

Magnitude
3.1 ml
Depth
24.0 km
shallow crustal
Location
56.0790°N
-154.4190°E
Intensity (MMI)
1.8
weak

Technical Information

Event ID
aka2026rafwcu
Event Type
earthquake
Status
✓ Reviewed
Significance
148
Stations Used
27
Azimuthal Gap
242.0°
Min Station Distance
0.500°
RMS Residual
1.00 sec
Last Updated
2026-08-28 19:53:37 UTC

Common Questions

How strong was the magnitude 3.1 earthquake near Akhiok, Alaska?

The magnitude 3.1 earthquake that struck 97 km S of Akhiok, Alaska on August 28, 2026 at 10:18 UTC had a depth of 24.0 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 3.1 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 3.1 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: aka2026rafwcu). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2026, August 28, 2026). M3.1 Earthquake 97 km S of Akhiok, AlaskaAugust 28, 2026. Retrieved August 28, 2026 from https://www.earthquaketracker.org/earthquakes/event/aka2026rafwcu/