Arkansas earthquakes

M3.0 earthquake 3 km NNE of Greenbrier, Arkansas

A magnitude 3.0 earthquake struck 3 km NNE of Greenbrier, Arkansas on Thu, Mar 3, 2011, 9:31 AM CST (15:31 UTC), 6 km (4 mi) below the surface.

A larger quake followed: M3.9 3 km NE of Greenbrier, Arkansas. This one was a foreshock.

Greenbrier forecast More in Arkansas

Map

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

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The earthquake

Magnitude: 3.0 (Md, duration), minor
Magnitude from: NM
Local time: Thu, Mar 3, 2011, 9:31 AM CST
UTC: 2011-03-03 15:31:49 UTC
Depth: 6.0 km (3.7 mi), shallow
Epicenter: 35.266° N, 92.371° W
Region: Arkansas
Felt reports: 15
Tsunami flag: No
Status: Reviewed by a seismologist

Magnitude estimates

Different scales measure different things and differ by a few tenths. The USGS marks one as preferred, and it is the one this page uses.

Mag.	Scale	Computed by	Notes
3.0	Md, duration	NM	Preferred · Reviewed · ±0.208 · 6 stations
3.1	Mwr, regional moment	USGS National Earthquake Information Center	Reviewed

What happened

The USGS’s account of the effects of this earthquake.

Felt (II) at Greenbrier. Also felt at Conway, Marshall and Quitman.

From the USGS event page for nm608570. U.S. Geological Survey text and figures are in the public domain.

Did you feel it?

15 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
Nodal plane 1: Strike 230°, dip 85°, rake 175°
Nodal plane 2: Strike 320°, dip 85°, rake 5°

How well it is located

Reviewed by a seismologist.

Location uncertainty: About 0.4 km horizontally, 0.3 km in depth
Magnitude uncertainty: ±0.21
Depth from: From location
Station coverage gap: 54°
Stations used: 17

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 200 in the 60 days after this one and at least 200 in the 30 days before it.

After

The first 60 of at least 200.

Before

Earthquakes today Arkansas earthquakes Live radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event nm608570 (also filed as nm030311k, usp000hva1). Read Thu, Oct 1, 2026, 2:06 PM UTC.