QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

Earthquake near Magnolia, AR

No earthquake was likely felt in Magnolia in the 24 hours to 3:42 pm CST (21:42 UTC). The last one was M 3.4, 139 km (86 mi) S, at 3:00 pm CDT on 21 August 2026, estimated intensity II (weak) in town; 78 felt reports to USGS. Every earthquake near Magnolia

This page: a magnitude 2.1 earthquake was recorded 10 km (6 mi) southeast of Magnolia, AR, at 3:57 pm CDT on 4 August 2021 (20:57 UTC), 7.7 km deep. 2 people have reported feeling it to USGS.

USGS: 9 km SE of Magnolia, Arkansas

3:57 pm CDT, Aug 4, 2021 · · 7.7 km deep · released about 47 lb of TNT

10 km30 km60 km120 km N Columbia County 8 kmLafayette County 43 kmClaiborne Parish 46 kmOuachita County 49 kmUnion County 52 kmNevada County 52 kmWebster Parish 57 kmMiller County 70 kmCalhoun County 70 km
Distance rings around the epicentre, with the nearest towns at their true direction. Not a shaking map — see the USGS ShakeMap for that.
When
3:57 pm CDT on 4 August 2021 ()
Where
10 km (6 mi) southeast of Magnolia, AR · earthquakes near Magnolia
Magnitude
M 2.1 (md)
Depth
7.7 km below the surface
Felt
2 reports · strongest reported intensity IV
Nearest
Columbia County, 8 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1855 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 29 km (18 mi) from the epicentre. In Magnolia, 10 km away, the estimate is intensity II (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

Earthquakes near other towns within 30 km: Waldo, Haynesville.

How big was it?

This earthquake released about 47 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 320,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 230,000× the energy of this one
  3. Around the size people start to feel M 3.0 20× the energy of this one
  4. This earthquake M 2.1 about 47 lb of TNT

Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.

For this area

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record since 1900 lists no earthquake of M5 or more within 50 km.

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 33.2172, -93.1517. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Columbia County, AR 8 km (5 mi) W earthquakes near Columbia County
Lafayette County, AR 43 km (27 mi) W earthquakes near Lafayette County
Claiborne Parish, LA 46 km (29 mi) SSE earthquakes near Claiborne Parish
Ouachita County, AR 49 km (30 mi) NNE earthquakes near Ouachita County
Union County, AR 52 km (32 mi) E earthquakes near Union County
Nevada County, AR 52 km (32 mi) NNW earthquakes near Nevada County

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

No further earthquakes have been recorded within 50 km since this one.

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.