QuakeIndex

Earthquake · reviewed by a seismologist

M 3.0mb_lg

Earthquake near Anthony, KS

No earthquake was likely felt in Anthony in the 24 hours to 7:26 pm CST (01:26 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 3.0 earthquake was recorded 21 km (13 mi) southeast of Anthony, KS, at 12:44 pm CDT on 14 August 2021 (17:44 UTC), 9.9 km deep. 3 people have reported feeling it to USGS.

USGS: 5 km SSE of Bluff City, Kansas

85 km (53 mi) SSW of Wichita, KS

12:44 pm CDT, Aug 14, 2021 · · 9.9 km deep · released about 950 lb of TNT

10 km30 km60 km120 km N Harper County 26 kmGrant County 28 kmSumner County 38 kmAlfalfa County 55 kmKingman County 63 kmKay County 67 kmGarfield County 74 kmBarber County 77 kmSedgwick 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
12:44 pm CDT on 14 August 2021 ()
Where
21 km (13 mi) southeast of Anthony, KS · earthquakes near Anthony
Magnitude
M 3.0 (mb_lg)
Depth
9.9 km below the surface
Felt
3 reports · strongest reported intensity III
Nearest
Harper County, 26 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1840 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 73 km (45 mi) from the epicentre. In Anthony, 21 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 21 km, intensity III · Caldwell 21 km, intensity III · Conway Springs 43 km, intensity II · Wellington 49 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 950 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 350,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 16,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 11,000× the energy of this one
  4. This earthquake M 3.0 about 950 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 130 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 37.0381, -97.8453. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Harper County, KS 26 km (16 mi) NW earthquakes near Harper County
Grant County, OK 28 km (18 mi) S earthquakes near Grant County
Sumner County, KS 38 km (24 mi) NE earthquakes near Sumner County
Alfalfa County, OK 55 km (34 mi) SW earthquakes near Alfalfa County
Kingman County, KS 63 km (39 mi) NNW earthquakes near Kingman County
Kay County, OK 67 km (42 mi) ESE earthquakes near Kay 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. 1.7 7 km E of Nescatunga, Oklahoma
  2. 1.7 9 km W of Lamont, Oklahoma
  3. 1.9 10 km W of Lamont, Oklahoma
  4. 1.6 4 km NNW of Wakita, Oklahoma
  5. 2.3 7 km ENE of Nescatunga, Oklahoma
  6. 2.1 10 km W of Lamont, Oklahoma
  7. 1.9 10 km W of Lamont, Oklahoma
  8. 2.7 5 km SW of Manchester, Oklahoma
  9. 1.5 2 km NW of Renfrow, Oklahoma
  10. 1.5 10 km W of Lamont, Oklahoma
  11. 2.4 8 km E of Nescatunga, Oklahoma
  12. 3.0 9 km ESE of Jefferson, Oklahoma
  13. 1.9 10 km ESE of Jefferson, Oklahoma
  14. 2.0 10 km W of Lamont, Oklahoma
  15. 1.5 9 km ESE of Jefferson, 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.