QuakeIndex

Earthquake · reviewed by a seismologist

M 2.8mb_lg

11 km N of Alex, Oklahoma

· 7.9 km deep · released about 480 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Grady County 8 kmMcClain County 32 kmCleveland County 48 kmCaddo County 55 kmGarvin County 56 kmStephens County 60 kmCanadian County 60 kmOklahoma County 69 kmComanche County 73 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 2.8 (mb_lg)
Depth
7.9 km below the surface
Felt
7 reports · strongest reported intensity III
Nearest
Grady County, 8 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3232 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 7 people have reported feeling it to USGS.

How big was it?

This earthquake released about 480 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 32,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 22,000× the energy of this one
  3. Around the size people start to feel M 3.0 2× the energy of this one
  4. This earthquake M 2.8 about 480 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 35.0199, -97.7993. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Grady County, OK 8 km (5 mi) E of here earthquakes near Grady County
McClain County, OK 32 km (20 mi) W of here earthquakes near McClain County
Cleveland County, OK 48 km (30 mi) WSW of here earthquakes near Cleveland County
Caddo County, OK 55 km (34 mi) ESE of here earthquakes near Caddo County
Garvin County, OK 56 km (35 mi) NW of here earthquakes near Garvin County
Stephens County, OK 60 km (37 mi) N of here earthquakes near Stephens County

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

Aftershocks so far

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

  1. 2.3 5 km N of Union City, Oklahoma
  2. 2.8 7 km NNE of Union City, Oklahoma
  3. 2.9 1 km NW of Minco, Oklahoma
  4. 2.1 7 km S of Washington, Oklahoma
  5. 3.2 6 km N of Foster, Oklahoma
  6. 2.7 6 km N of Foster, Oklahoma
  7. 2.5 5 km N of Foster, Oklahoma
  8. 2.6 8 km SSW of Dibble, Oklahoma
  9. 2.5 13 km W of Union City, Oklahoma
  10. 2.4 4 km SE of Minco, Oklahoma
  11. 2.4 6 km NNW of Alex, Oklahoma
  12. 2.5 3 km SSW of Dibble, Oklahoma
  13. 2.4 5 km WSW of Minco, Oklahoma
  14. 3.0 5 km NW of Alex, Oklahoma
  15. 2.5 6 km NW of Alex, 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.