QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5md

Earthquake near Pocahontas, AR

USGS: 7 km E of Maynard, Arkansas

1:38 am CST, Nov 12, 2020 · · 15 km deep · released about 160 lb of TNT

10 km30 km60 km120 km N Randolph County 21 kmRipley County 25 kmClay County 36 kmGreene County 41 kmButler County 49 kmLawrence County 50 kmCarter County 59 kmOregon County 60 kmSharp County 65 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
1:38 am CST on 12 November 2020 ()
Where
23 km (14 mi) NE of Pocahontas, AR · earthquakes near Pocahontas
Magnitude
M 2.5 (md)
Depth
15 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Randolph County, 21 km WSW
Nearest mapped fault
Western Lowlands liquefaction features, 7 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2074 days ago

A magnitude 2.5 earthquake was recorded 23 km (14 mi) NE of Pocahontas, AR, at 1:38 am CST on 12 November 2020 (07:38 UTC). 1 person has reported feeling it to USGS. This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

Earthquakes near other towns within 30 km: Corning, Doniphan.

How big was it?

This earthquake released about 160 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 92,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 65,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.8× the energy of this one
  4. This earthquake M 2.5 about 160 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 36.4288, -90.8158. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Randolph County, AR 21 km (13 mi) WSW earthquakes near Randolph County
Ripley County, MO 25 km (16 mi) NNW earthquakes near Ripley County
Clay County, AR 36 km (22 mi) E earthquakes near Clay County
Greene County, AR 41 km (25 mi) SSE earthquakes near Greene County
Butler County, MO 49 km (30 mi) NE earthquakes near Butler County
Lawrence County, AR 50 km (31 mi) SSW earthquakes near Lawrence County

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

Aftershocks so far

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

  1. 2.1 9 km NNW of Ravenden Springs, Arkansas
  2. 1.8 2 km W of Imboden, Arkansas
  3. 2.0 Missouri-Arkansas border region
  4. 2.0 2 km NNW of Black Rock, Arkansas
  5. 2.5 4 km SSW of Maynard, Arkansas
  6. 2.8 0.4 km ESE of Maynard, Arkansas
  7. 1.9 5 km S of Imboden, Arkansas
  8. 2.0 3 km SSW of Imboden, Arkansas
  9. 3.1 4 km SSW of Imboden, Arkansas
  10. 2.1 18 km WNW of Maynard, Arkansas
  11. 1.7 Missouri-Arkansas border region
  12. 1.7 2 km WSW of Imboden, Arkansas
  13. 2.1 2 km SE of Ravenden, Arkansas
  14. 1.9 3 km ESE of Ravenden, Arkansas
  15. 1.8 Missouri-Arkansas border region

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.