QuakeIndex

quarry blast · reviewed by a seismologist

M 1.8ml

Earthquake near Caddo, OK

No earthquake was likely felt in Caddo in the 24 hours to 10:14 am CST (16:14 UTC). The last one was M 3.4, 231 km (144 mi) NW, at 5:53 am CST on 7 November 2026, estimated intensity II (weak) in town; 23 felt reports to USGS. Every earthquake near Caddo

No: USGS classifies this as a quarry blast, not an earthquake. A magnitude 1.8 quarry blast was recorded 3 km (2 mi) south of Caddo, OK, at 4:49 pm CDT on 21 September 2023 (21:49 UTC), less than 1 km deep.

USGS: 3 km S of Caddo, Oklahoma

4:49 pm CDT, Sep 21, 2023 · · 0.0 km deep · released about 15 lb of TNT

10 km30 km60 km120 km N Bryan County 15 kmAtoka County 39 kmJohnston County 43 kmMarshall County 47 kmCoal County 54 kmFannin County 58 kmGrayson County 65 kmChoctaw County 66 kmPontotoc County 80 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
4:49 pm CDT on 21 September 2023 ()
Where
3 km (2 mi) south of Caddo, OK · earthquakes near Caddo
Oklahoma today
every earthquake in Oklahoma in the last 24 hours
Magnitude
M 1.8 (ml)
Depth
0.0 km below the surface
Felt
no reports yet
Nearest
Bryan County, 15 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1144 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 16 km (10 mi) from the epicentre. In Caddo, 3 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: Durant, Calera.

USGS catalogues this as quarry blast, not an earthquake.

How big was it?

This earthquake released about 15 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 730,000× the energy of this one
  3. Around the size people start to feel M 3.0 65× the energy of this one
  4. This earthquake M 1.8 about 15 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 34.0982, -96.2645. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Bryan County, OK 15 km (9 mi) S earthquakes near Bryan County
Atoka County, OK 39 km (24 mi) NNE earthquakes near Atoka County
Johnston County, OK 43 km (27 mi) NW earthquakes near Johnston County
Marshall County, OK 47 km (29 mi) W earthquakes near Marshall County
Coal County, OK 54 km (34 mi) N earthquakes near Coal County
Fannin County, TX 58 km (36 mi) SSE earthquakes near Fannin County

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

Aftershocks so far

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

  1. 1.4 9 km SSE of Wapanucka, Oklahoma
  2. 1.2 10 km S of Wapanucka, Oklahoma
  3. 1.2 6 km SSW of Wapanucka, Oklahoma
  4. 1.3 6 km SSW of Wapanucka, Oklahoma
  5. 1.5 9 km SSE of Wapanucka, Oklahoma
  6. 1.5 9 km SSE of Wapanucka, Oklahoma
  7. 1.5 6 km SSE of Tishomingo, Oklahoma
  8. 1.6 10 km SSE of Wapanucka, Oklahoma
  9. 1.5 9 km SSE of Wapanucka, Oklahoma
  10. 1.5 4 km W of Durant, Oklahoma
  11. 1.6 2 km NNW of Durant, Oklahoma
  12. 1.7 1 km WSW of Durant, Oklahoma
  13. 2.0 2 km SW of Durant, Oklahoma
  14. 2.4 4 km WSW of Durant, Oklahoma
  15. 1.7 3 km SW of Armstrong, 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.