Alaska earthquakes

M4.3 earthquake 30 km WNW of Willow, Alaska

A magnitude 4.3 earthquake struck 30 km WNW of Willow, Alaska on Wed, Aug 11, 2021, 10:13 PM AKDT (06:13 UTC), 60 km (37 mi) below the surface.

Willow forecast More in Alaska

Map

Where this earthquake was located, with the others nearby. Select one for its page.

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The earthquake

Magnitude: 4.3 (ml), light
Local time: Wed, Aug 11, 2021, 10:13 PM AKDT
UTC: 2021-08-12 06:13:59 UTC
Depth: 59.7 km (37.1 mi), shallow
Epicenter: 61.870° N, 150.553° W
Region: Alaska
Felt reports: 401
Strongest shaking: III, weak shaking
Tsunami flag: No
Status: Reviewed by a seismologist

Shaking

The USGS ShakeMap: shaking estimated from seismic stations and the quake’s size, on the Modified Mercalli intensity scale.

Strongest estimated: III, weak shaking
Peak ground acceleration: 0.9% of gravity
Peak ground velocity: -0.9 cm/s
Map: Automatic

USGS ShakeMap: estimated shaking intensity around the epicenter — Estimated shaking intensity. Map: USGS ShakeMap.

Did you feel it?

401 people reported to the USGS what they felt; the strongest reported shaking was III, weak shaking.

Fault motion and ground failure

How the rock slipped, from the moment tensor, and the USGS estimate of landslides and liquefaction.

Faulting: Strike-slip
Moment magnitude: 4.2 Mwr
Nodal plane 1: Strike 59°, dip 56°, rake -13°
Nodal plane 2: Strike 156°, dip 79°, rake -146°

How well it is located

Reviewed by a seismologist.

Stations used: 176

Nearest places

Distance and direction from each place to the epicenter, with its forecast.

Nearby

Within 100 km, magnitude 1.5 and up: at least 199 in the 60 days after this one and 108 in the 30 days before it.

After

The first 60 of at least 199.

Before

Earthquakes today Alaska earthquakes Live radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event ak021aak1945 (also filed as us6000f4ez). Read Fri, Sep 25, 2026, 2:26 PM UTC.