QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9mb_lg

Earthquake near Anthony, KS

No earthquake was likely felt in Anthony in the 24 hours to 10:09 am CST (16:09 UTC). The last one was M 3.4, 172 km (107 mi) S, at 5:53 am CST on 7 November 2026, estimated intensity II (weak) in town; 23 felt reports to USGS. Every earthquake near Anthony

This page: a magnitude 2.9 earthquake was recorded 18 km (11 mi) south-southeast of Anthony, KS, at 1:21 pm CST on 30 December 2021 (19:21 UTC), 5.0 km deep. 1 person has reported feeling it to USGS.

USGS: 6 km E of Manchester, Oklahoma

94 km (58 mi) SW of Wichita, KS

1:21 pm CST, Dec 30, 2021 · · 5.0 km deep · released about 680 lb of TNT

10 km30 km60 km120 km N Harper County 22 kmGrant County 29 kmAlfalfa County 44 kmSumner County 49 kmKingman County 63 kmBarber County 68 kmGarfield County 71 kmKay County 76 kmWoods County 86 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
1:21 pm CST on 30 December 2021 ()
Where
18 km (11 mi) south-southeast of Anthony, KS · earthquakes near Anthony
Oklahoma today
every earthquake in Oklahoma in the last 24 hours
Magnitude
M 2.9 (mb_lg)
Depth
5.0 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Harper County, 22 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1712 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 67 km (42 mi) from the epicentre. In Anthony, 18 km away, the estimate is intensity III (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.

Likely felt in: Anthony 18 km, intensity III · Caldwell 32 km, intensity III · Cherokee 44 km, intensity II. Estimated for each town centre; each link is that town's own record.

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.

For this area

The largest earthquake within 50 km since 2016 was M 4.4 on 2019-05-17 — about 180 times the energy of this one.

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 37.0042, -97.9668. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Harper County, KS 22 km (14 mi) NNW earthquakes near Harper County
Grant County, OK 29 km (18 mi) SSE earthquakes near Grant County
Alfalfa County, OK 44 km (27 mi) SW earthquakes near Alfalfa County
Sumner County, KS 49 km (31 mi) ENE earthquakes near Sumner County
Kingman County, KS 63 km (39 mi) NNW earthquakes near Kingman County
Barber County, KS 68 km (42 mi) WNW earthquakes near Barber County

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

Aftershocks so far

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

  1. 1.8 10 km ESE of Jefferson, Oklahoma
  2. 1.6 7 km NW of Medford, Oklahoma
  3. 1.6 1 km WNW of Renfrow, Oklahoma
  4. 2.4 6 km NNE of Argonia, Kansas
  5. 1.9 7 km NW of Medford, Oklahoma
  6. 1.8 1 km SSW of Wakita, Oklahoma
  7. 1.8 7 km W of Jet, Oklahoma
  8. 1.8 6 km NW of Medford, Oklahoma
  9. 1.6 6 km NW of Medford, Oklahoma
  10. 1.7 10 km W of Lamont, Oklahoma
  11. 2.0 6 km NW of Medford, Oklahoma
  12. 1.9 7 km NW of Medford, Oklahoma
  13. 2.0 6 km NW of Medford, Oklahoma
  14. 2.9 7 km NW of Medford, Oklahoma
  15. 1.5 6 km NW of Medford, 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.