QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9ml

9 km SSW of Alex, Oklahoma

· 7.0 km deep · released about 21 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Grady County 20 kmMcClain County 39 kmStephens County 40 kmGarvin County 49 kmCleveland County 61 kmCaddo County 62 kmComanche County 63 kmCanadian County 79 kmCotton County 79 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 1.9 (ml)
Depth
7.0 km below the surface
Felt
no reports yet
Nearest
Grady County, 20 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1699 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 21 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 5.8 730,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 520,000× the energy of this one
  3. Around the size people start to feel M 3.0 46× the energy of this one
  4. This earthquake M 1.9 about 21 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 34.8438, -97.8272. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Grady County, OK 20 km (13 mi) SSE of here earthquakes near Grady County
McClain County, OK 39 km (24 mi) WSW of here earthquakes near McClain County
Stephens County, OK 40 km (25 mi) N of here earthquakes near Stephens County
Garvin County, OK 49 km (31 mi) WNW of here earthquakes near Garvin County
Cleveland County, OK 61 km (38 mi) SW of here earthquakes near Cleveland County
Caddo County, OK 62 km (39 mi) SE of here earthquakes near Caddo County

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

Aftershocks so far

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

  1. 1.6 10 km SSW of Bradley, Oklahoma
  2. 1.7 9 km ESE of Chickasha, Oklahoma
  3. 1.9 10 km ESE of Chickasha, Oklahoma
  4. 1.7 12 km SSW of Bradley, Oklahoma
  5. 2.2 11 km ESE of Chickasha, Oklahoma
  6. 1.7 10 km ESE of Chickasha, Oklahoma
  7. 1.7 11 km ESE of Chickasha, Oklahoma
  8. 1.6 5 km SW of Bridge Creek, Oklahoma
  9. 1.6 5 km WSW of Bridge Creek, Oklahoma
  10. 1.6 5 km WSW of Bridge Creek, Oklahoma
  11. 1.6 7 km SSW of Bridge Creek, Oklahoma
  12. 1.6 12 km SSW of Bradley, Oklahoma
  13. 1.8 10 km NNW of Alex, Oklahoma
  14. 1.6 10 km ESE of Chickasha, Oklahoma
  15. 1.6 10 km NE of Ninnekah, 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.