QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5ml

Earthquake near Holdenville, OK

USGS: 5 km ENE of Horntown, Oklahoma

12:19 am CDT, Apr 6, 2018 · · 3.3 km deep · released about 170 lb of TNT

10 km30 km60 km120 km N Hughes County 8 kmSeminole County 37 kmOkfuskee County 41 kmPittsburg County 46 kmMcIntosh County 56 kmCoal County 59 kmPontotoc County 63 kmOkmulgee County 63 kmPottawatomie County 70 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
12:19 am CDT on 6 April 2018 ()
Where
19 km (12 mi) E of Holdenville, OK · earthquakes near Holdenville
Magnitude
M 2.5 (ml)
Depth
3.3 km below the surface
Felt
2 reports · strongest reported intensity IV
Nearest
Hughes County, 8 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3017 days ago

A magnitude 2.5 earthquake was recorded 19 km (12 mi) E of Holdenville, OK, at 12:19 am CDT on 6 April 2018 (05:19 UTC). 2 people have reported feeling it to USGS. This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

Earthquakes near other towns within 30 km: Wetumka, Wewoka.

How big was it?

This earthquake released about 170 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 89,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 63,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.6× the energy of this one
  4. This earthquake M 2.5 about 170 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

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 35.1108, -96.1972. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Hughes County, OK 8 km (5 mi) SW earthquakes near Hughes County
Seminole County, OK 37 km (23 mi) W earthquakes near Seminole County
Okfuskee County, OK 41 km (26 mi) NNW earthquakes near Okfuskee County
Pittsburg County, OK 46 km (28 mi) ESE earthquakes near Pittsburg County
McIntosh County, OK 56 km (35 mi) ENE earthquakes near McIntosh County
Coal County, OK 59 km (37 mi) S earthquakes near Coal 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. 3.6 7 km WSW of Horntown, Oklahoma
  2. 1.5 3 km ESE of Lamar, Oklahoma
  3. 1.9 3 km SE of Lamar, Oklahoma
  4. 1.9 4 km SE of Lamar, Oklahoma
  5. 2.5 6 km S of Yeager, Oklahoma
  6. 1.6 Oklahoma
  7. 2.3 5 km WNW of Cromwell, Oklahoma
  8. 1.7 6 km SSE of Yeager, Oklahoma
  9. 2.2 7 km SSW of Dustin, Oklahoma
  10. 1.5 7 km SE of Calvin, Oklahoma
  11. 2.0 9 km WNW of Ashland, Oklahoma
  12. 1.9 6 km SSE of Yeager, Oklahoma
  13. 2.0 7 km N of Atwood, Oklahoma
  14. 2.2 7 km N of Atwood, Oklahoma
  15. 1.7 4 km NW of Cromwell, 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.