QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9mb_lg

1 km S of Medford, Oklahoma

· 5.0 km deep · released about 680 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Grant County 5 kmGarfield County 46 kmKay County 52 kmAlfalfa County 53 kmHarper County 53 kmSumner County 54 kmNoble County 63 kmMajor County 90 kmKingman County 92 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 2.9 (mb_lg)
Depth
5.0 km below the surface
Felt
2 reports · strongest reported intensity II
Nearest
Grant County, 5 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1511 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 2 people have reported feeling it to USGS.

How big was it?

This earthquake released about 680 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 22,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 16,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.4× the energy of this one
  4. This earthquake M 2.9 about 680 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 36.7915, -97.7327. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Grant County, OK 5 km (3 mi) E of here earthquakes near Grant County
Garfield County, OK 46 km (29 mi) N of here earthquakes near Garfield County
Kay County, OK 52 km (33 mi) W of here earthquakes near Kay County
Alfalfa County, OK 53 km (33 mi) E of here earthquakes near Alfalfa County
Harper County, KS 53 km (33 mi) SE of here earthquakes near Harper County
Sumner County, KS 54 km (33 mi) SSW of here earthquakes near Sumner County

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

Aftershocks so far

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

  1. 2.2 6 km NE of South Haven, Kansas
  2. 1.5 7 km ENE of Bluff City, Kansas
  3. 1.8 6 km WNW of Renfrow, Oklahoma
  4. 1.5 5 km W of South Haven, Kansas
  5. 1.9 2 km SSE of Bluff City, Kansas
  6. 1.6 3 km ENE of Freeport, Kansas
  7. 1.8 3 km E of Freeport, Kansas
  8. 2.3 4 km NE of Medford, Oklahoma
  9. 2.2 7 km N of Wakita, Oklahoma
  10. 2.5 1 km N of Goltry, Oklahoma
  11. 1.5 7 km ENE of Bluff City, Kansas
  12. 2.3 10 km SSE of Waldron, Kansas
  13. 2.3 7 km NE of Caldwell, Kansas
  14. 3.3 3 km ENE of South Haven, Kansas
  15. 2.0 2 km NW of Jet, 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.4 on 2018-06-09 — it released about 180 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.