QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9ml

Earthquake near Hartshorne, OK

No earthquake was likely felt in Hartshorne in the 24 hours to 6:32 pm CST (00:32 UTC). The last one was M 3.4, 241 km (150 mi) WNW, at 5:53 am CST on 7 November 2026, estimated intensity II (weak) in town; 23 felt reports to USGS. Every earthquake near Hartshorne

This page: a magnitude 1.9 earthquake was recorded 3 km (2 mi) north-northeast of Hartshorne, OK, at 10:11 am CDT on 6 August 2021 (15:11 UTC), 17 km deep.

USGS: 2 km NNE of Hartshorne, Oklahoma

10:11 am CDT, Aug 6, 2021 · · 17 km deep · released about 20 lb of TNT

10 km30 km60 km120 km N Pittsburg County 19 kmLatimer County 25 kmPushmataha County 56 kmMcIntosh County 57 kmHaskell County 57 kmHughes County 67 kmAtoka County 69 kmCoal County 75 kmLe Flore County 78 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
10:11 am CDT on 6 August 2021 ()
Where
3 km (2 mi) north-northeast of Hartshorne, OK · earthquakes near Hartshorne
Oklahoma today
every earthquake in Oklahoma in the last 24 hours
Magnitude
M 1.9 (ml)
Depth
17 km below the surface
Felt
no reports yet
Nearest
Pittsburg County, 19 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1923 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 11 km (7 mi) from the epicentre. In Hartshorne, 3 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: Krebs, McAlester, Wilburton.

How big was it?

This earthquake released about 20 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 760,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 540,000× the energy of this one
  3. Around the size people start to feel M 3.0 48× the energy of this one
  4. This earthquake M 1.9 about 20 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 34.8697, -95.5482. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Pittsburg County, OK 19 km (12 mi) WNW earthquakes near Pittsburg County
Latimer County, OK 25 km (16 mi) E earthquakes near Latimer County
Pushmataha County, OK 56 km (35 mi) SSE earthquakes near Pushmataha County
McIntosh County, OK 57 km (35 mi) NNW earthquakes near McIntosh County
Haskell County, OK 57 km (35 mi) NE earthquakes near Haskell County
Hughes County, OK 67 km (42 mi) WNW earthquakes near Hughes 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. 1.9 1 km SSW of Quinton, Oklahoma
  2. 1.9 1 km SSW of Quinton, Oklahoma
  3. 2.1 1 km S of Quinton, Oklahoma
  4. 1.6 1 km S of Quinton, Oklahoma
  5. 2.1 1 km SW of Quinton, Oklahoma
  6. 3.7 1 km S of Quinton, Oklahoma
  7. 1.6 1 km S of Quinton, Oklahoma
  8. 2.2 1 km S of Quinton, Oklahoma
  9. 2.2 1 km S of Quinton, Oklahoma
  10. 2.1 1 km S of Quinton, Oklahoma
  11. 2.3 1 km S of Quinton, Oklahoma
  12. 1.9 1 km S of Quinton, Oklahoma
  13. 1.9 1 km SSW of Quinton, Oklahoma
  14. 1.9 3 km NNE of Quinton, Oklahoma
  15. 2.0 2 km ESE of Quinton, Oklahoma

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.