QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

Earthquake near West Plains, MO

No earthquake was likely felt in West Plains in the 24 hours to 2:16 pm CST (20:16 UTC). The last one was M 2.2, 33 km (21 mi) S, at 9:10 pm CST on 1 November 2026, estimated intensity II (weak) in town. Every earthquake near West Plains

This page: a magnitude 2.1 earthquake was recorded 34 km (21 mi) south-southwest of West Plains, MO, at 11:49 am CST on 20 December 2020 (17:49 UTC), 5.0 km deep. 3 people have reported feeling it to USGS.

USGS: 4 km N of Viola, Arkansas

11:49 am CST, Dec 20, 2020 · · 5.0 km deep · released about 51 lb of TNT

10 km30 km60 km120 km N Fulton County 16 kmBaxter County 36 kmHowell County 38 kmIzard County 39 kmOzark County 48 kmSharp County 55 kmOregon County 59 kmMarion County 65 kmStone County 66 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
11:49 am CST on 20 December 2020 ()
Where
34 km (21 mi) south-southwest of West Plains, MO · earthquakes near West Plains
Magnitude
M 2.1 (md)
Depth
5.0 km below the surface
Felt
3 reports · strongest reported intensity II
Nearest
Fulton County, 16 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2083 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 30 km (19 mi) from the epicentre. In West Plains, 34 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.

How big was it?

This earthquake released about 51 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 5.8 300,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 210,000× the energy of this one
  3. Around the size people start to feel M 3.0 19× the energy of this one
  4. This earthquake M 2.1 about 51 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 36.4388, -91.9838. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Fulton County, AR 16 km (10 mi) ESE earthquakes near Fulton County
Baxter County, AR 36 km (22 mi) WSW earthquakes near Baxter County
Howell County, MO 38 km (24 mi) NNE earthquakes near Howell County
Izard County, AR 39 km (24 mi) S earthquakes near Izard County
Ozark County, MO 48 km (30 mi) WNW earthquakes near Ozark County
Sharp County, AR 55 km (34 mi) ESE earthquakes near Sharp County

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

Aftershocks so far

16 earthquakes have been recorded within 50 km since this one.

  1. 2.2 7 km NNW of Salem, Arkansas
  2. 2.1 2 km E of Mountain Home, Arkansas
  3. 1.9 9 km SW of Koshkonong, Missouri
  4. 1.9 10 km NNE of Salem, Arkansas
  5. 2.3 11 km NNE of Salem, Arkansas
  6. 2.0 4 km N of Evening Shade, Arkansas
  7. 2.2 2 km WSW of Gainesville, Missouri
  8. 2.1 4 km N of Midway, Arkansas
  9. 2.2 7 km ENE of West Plains, Missouri
  10. 1.8 11 km WSW of Melbourne, Arkansas
  11. 2.2 6 km WNW of West Plains, Missouri
  12. 2.3 4 km SE of Franklin, Arkansas
  13. 2.2 4 km SE of Ash Flat, Arkansas
  14. 2.1 7 km ENE of Midway, Arkansas
  15. 2.1 5 km SE of Ash Flat, Arkansas

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.