QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

3 km N of Black Rock, Arkansas

· 9.7 km deep · released about 13 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lawrence County 11 kmRandolph County 23 kmSharp County 34 kmGreene County 48 kmCraighead County 55 kmRipley County 60 kmIndependence County 61 kmJackson County 62 kmClay 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
Magnitude
M 1.8 (md)
Depth
9.7 km below the surface
Felt
no reports yet
Nearest
Lawrence County, 11 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1224 days ago

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

How big was it?

This earthquake released about 13 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 840,000× the energy of this one
  3. Around the size people start to feel M 3.0 75× the energy of this one
  4. This earthquake M 1.8 about 13 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.

Where

Epicentre 36.1437, -91.0992. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lawrence County, AR 11 km (7 mi) N of here earthquakes near Lawrence County
Randolph County, AR 23 km (14 mi) SSW of here earthquakes near Randolph County
Sharp County, AR 34 km (21 mi) E of here earthquakes near Sharp County
Greene County, AR 48 km (30 mi) W of here earthquakes near Greene County
Craighead County, AR 55 km (34 mi) NW of here earthquakes near Craighead County
Ripley County, MO 60 km (37 mi) SSW of here earthquakes near Ripley County

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

Aftershocks so far

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

  1. 2.2 2 km W of Lynn, Arkansas
  2. 1.8 2 km SW of Lynn, Arkansas
  3. 1.8 2 km W of Lynn, Arkansas
  4. 1.7 3 km WNW of Lynn, Arkansas
  5. 2.2 4 km SSE of Maynard, Arkansas
  6. 2.1 3 km WNW of Lynn, Arkansas
  7. 2.0 4 km NW of Lynn, Arkansas
  8. 1.9 4 km NW of Lynn, Arkansas
  9. 1.5 3 km WNW of Lynn, Arkansas
  10. 1.8 2 km W of Lynn, Arkansas
  11. 2.0 3 km WNW of Lynn, Arkansas
  12. 1.8 9 km ESE of Ash Flat, Arkansas
  13. 2.0 8 km ESE of Ash Flat, Arkansas
  14. 1.7 4 km SSW of Strawberry, Arkansas
  15. 2.1 6 km ENE of Smithville, 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.