QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6ml

Earthquake near Thomas, OK

No earthquake was likely felt in Thomas in the 24 hours to 10:47 am CST (16:47 UTC). The last one was M 3.4, 65 km (41 mi) ESE, at 5:53 am CST on 7 November 2026, estimated intensity II (weak) in town; 23 felt reports to USGS. Every earthquake near Thomas

This page: a magnitude 1.6 earthquake was recorded 11 km (7 mi) south of Thomas, OK, at 7:39 am CDT on 8 October 2020 (12:39 UTC), 6.7 km deep.

USGS: 10 km S of Thomas, Oklahoma

7:39 am CDT, Oct 8, 2020 · · 6.7 km deep · released about 8.7 lb of TNT

10 km30 km60 km120 km N Custer County 23 kmBlaine County 38 kmDewey County 44 kmWashita County 46 kmCaddo County 63 kmCanadian County 70 kmMajor County 76 kmKingfisher County 80 kmKiowa County 84 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
7:39 am CDT on 8 October 2020 ()
Where
11 km (7 mi) south of Thomas, OK · earthquakes near Thomas
Oklahoma today
every earthquake in Oklahoma in the last 24 hours
Magnitude
M 1.6 (ml)
Depth
6.7 km below the surface
Felt
no reports yet
Nearest
Custer County, 23 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2224 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 7 km (4 mi) from the epicentre. In Thomas, 11 km away, the estimate is intensity II (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.

Earthquakes near other towns within 30 km: Weatherford, Clinton.

How big was it?

This earthquake released about 8.7 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,700,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,200,000× the energy of this one
  3. Around the size people start to feel M 3.0 110× the energy of this one
  4. This earthquake M 1.6 about 8.7 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 35.6478, -98.7422. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Custer County, OK 23 km (14 mi) W earthquakes near Custer County
Blaine County, OK 38 km (24 mi) NE earthquakes near Blaine County
Dewey County, OK 44 km (27 mi) NNW earthquakes near Dewey County
Washita County, OK 46 km (28 mi) SSW earthquakes near Washita County
Caddo County, OK 63 km (39 mi) SSE earthquakes near Caddo County
Canadian County, OK 70 km (43 mi) E earthquakes near Canadian County

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

Aftershocks so far

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

  1. 1.6 14 km WNW of Greenfield, Oklahoma
  2. 1.6 7 km NNE of Custer City, Oklahoma
  3. 2.4 7 km ESE of Thomas, Oklahoma
  4. 1.9 8 km ESE of Thomas, Oklahoma
  5. 2.3 8 km ESE of Thomas, Oklahoma
  6. 2.1 9 km ESE of Thomas, Oklahoma
  7. 1.6 6 km ESE of Thomas, Oklahoma
  8. 2.1 8 km ESE of Thomas, Oklahoma
  9. 2.3 9 km ESE of Thomas, Oklahoma
  10. 1.6 8 km ESE of Thomas, Oklahoma
  11. 1.6 8 km ESE of Thomas, Oklahoma
  12. 1.7 8 km ESE of Thomas, Oklahoma
  13. 1.7 12 km NW of Watonga, Oklahoma
  14. 1.5 15 km W of Canton, Oklahoma
  15. 1.7 7 km WSW of Custer City, 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.