QuakeIndex

mining explosion · reviewed by a seismologist

M 3.0ml

Earthquake near Gillette, WY

No earthquake was likely felt in Gillette in the 24 hours to 9:35 pm MST (04:35 UTC). The last one was M 3.4, 45 km (28 mi) SSE, at 2:13 pm MDT on 6 July 2026, estimated intensity II (weak) in town. Every earthquake near Gillette

No: USGS classifies this as a mining explosion, not an earthquake. A magnitude 3.0 mining explosion was recorded 23 km (14 mi) north of Gillette, WY, at 12:00 pm MDT on 14 August 2025 (18:00 UTC), less than 1 km deep.

USGS: 22 km N of Gillette, Wyoming

12:00 pm MDT, Aug 14, 2025 · · 0.0 km deep · released about 950 lb of TNT

10 km30 km60 km120 km N Campbell County 34 kmCrook County 79 kmJohnson County 97 kmPowder River County 102 kmWeston County 106 kmSheridan County 110 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
12:00 pm MDT on 14 August 2025 ()
Where
23 km (14 mi) north of Gillette, WY · earthquakes near Gillette
Magnitude
M 3.0 (ml)
Depth
0.0 km below the surface
Felt
no reports yet
Nearest
Campbell County, 34 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 373 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 37 km (23 mi) from the epicentre. In Gillette, 23 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.

USGS catalogues this as mining explosion, not an earthquake.

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

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

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 5.0 37 km W of Gillette, Wyoming · 44 km SW of this epicentre

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 44.4926, -105.5506. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Campbell County, WY 34 km (21 mi) S earthquakes near Campbell County
Crook County, WY 79 km (49 mi) E earthquakes near Crook County
Johnson County, WY 97 km (60 mi) WSW earthquakes near Johnson County
Powder River County, MT 102 km (63 mi) N earthquakes near Powder River County
Weston County, WY 106 km (66 mi) SE earthquakes near Weston County
Sheridan County, WY 110 km (68 mi) WNW earthquakes near Sheridan County

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

Aftershocks so far

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

  1. 2.4 2 km WSW of Gillette, Wyoming
  2. 2.8 6 km SSE of Sleepy Hollow, Wyoming
  3. 3.1 15 km SSE of Antelope Valley-Crestview, Wyoming
  4. 2.5 13 km SE of Sleepy Hollow, Wyoming
  5. 3.1 9 km SSE of Antelope Valley-Crestview, Wyoming
  6. 3.2 18 km SSE of Antelope Valley-Crestview, Wyoming
  7. 2.7 19 km NNE of Gillette, Wyoming
  8. 2.6 17 km NNE of Gillette, Wyoming
  9. 2.8 9 km NW of Gillette, Wyoming
  10. 3.2 17 km SSE of Antelope Valley-Crestview, Wyoming
  11. 2.6 16 km S of Antelope Valley-Crestview, Wyoming
  12. 2.5 3 km NNE of Gillette, Wyoming
  13. 3.1 7 km SE of Antelope Valley-Crestview, Wyoming
  14. 2.8 10 km NNW of Gillette, Wyoming
  15. 3.3 12 km SSE of Antelope Valley-Crestview, Wyoming

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.