QuakeIndex

quarry blast · reviewed by a seismologist

M 1.5ml

Earthquake near Sulphur, OK

No earthquake was likely felt in Sulphur in the 24 hours to 10:43 pm CST (04:43 UTC). The last one was M 3.4, 157 km (97 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 Sulphur

No: USGS classifies this as a quarry blast, not an earthquake. A magnitude 1.5 quarry blast was recorded 14 km (9 mi) east-southeast of Sulphur, OK, at 12:40 pm CDT on 1 August 2023 (17:40 UTC), less than 1 km deep.

USGS: 6 km N of Mill Creek, Oklahoma

12:40 pm CDT, Aug 1, 2023 · · 0.0 km deep · released about 5.9 lb of TNT

10 km30 km60 km120 km N Johnston County 23 kmMurray County 23 kmPontotoc County 31 kmCarter County 48 kmMarshall County 48 kmCoal County 51 kmGarvin County 52 kmLove County 68 kmAtoka County 73 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
12:40 pm CDT on 1 August 2023 ()
Where
14 km (9 mi) east-southeast of Sulphur, OK · earthquakes near Sulphur
Oklahoma today
every earthquake in Oklahoma in the last 24 hours
Magnitude
M 1.5 (ml)
Depth
0.0 km below the surface
Felt
no reports yet
Nearest
Johnston County, 23 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1198 days ago

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

At this magnitude and depth it was probably too small to be felt, even directly above it. In Sulphur, 14 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: Davis, Tishomingo.

USGS catalogues this as quarry blast, not an earthquake.

How big was it?

This earthquake released about 5.9 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,500,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,800,000× the energy of this one
  3. Around the size people start to feel M 3.0 160× the energy of this one
  4. This earthquake M 1.5 about 5.9 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 34.4607, -96.8253. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Johnston County, OK 23 km (14 mi) SE earthquakes near Johnston County
Murray County, OK 23 km (14 mi) W earthquakes near Murray County
Pontotoc County, OK 31 km (20 mi) NNE earthquakes near Pontotoc County
Carter County, OK 48 km (30 mi) WSW earthquakes near Carter County
Marshall County, OK 48 km (30 mi) S earthquakes near Marshall County
Coal County, OK 51 km (32 mi) ENE earthquakes near Coal County

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

Aftershocks so far

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

  1. 2.1 10 km ESE of Katie, Oklahoma
  2. 1.5 8 km N of Mill Creek, Oklahoma
  3. 1.6 3 km SW of Mill Creek, Oklahoma
  4. 1.6 9 km SSE of Wapanucka, Oklahoma
  5. 2.3 7 km E of Ada, Oklahoma
  6. 1.5 4 km NE of Fitzhugh, Oklahoma
  7. 1.6 10 km SSE of Wapanucka, Oklahoma
  8. 1.5 8 km SSE of Wapanucka, Oklahoma
  9. 3.1 10 km SW of Lehigh, Oklahoma
  10. 2.2 8 km SE of Katie, Oklahoma
  11. 1.8 6 km SE of Katie, Oklahoma
  12. 1.7 11 km ENE of Pauls Valley, Oklahoma
  13. 2.0 9 km ESE of Katie, Oklahoma
  14. 1.9 8 km ESE of Katie, Oklahoma
  15. 1.8 8 km SE of Katie, 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.