QuakeIndex

mining explosion · reviewed by a seismologist

M 2.8ml

25 km SW of Birney, Montana

· 0.0 km deep · released about 480 lb of TNT

10 km30 km60 km120 km N Sheridan County 44 kmBig Horn County 66 kmPowder River County 97 kmRosebud County 113 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
Magnitude
M 2.8 (ml)
Depth
0.0 km below the surface
Felt
no reports yet
Nearest
Sheridan County, 44 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2262 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

USGS catalogues this as mining explosion, not an earthquake.

How big was it?

This earthquake released about 480 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 32,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 22,000× the energy of this one
  3. Around the size people start to feel M 3.0 2× the energy of this one
  4. This earthquake M 2.8 about 480 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.

Where

Epicentre 45.1606, -106.7446. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Sheridan County, WY 44 km (27 mi) NNE of here earthquakes near Sheridan County
Big Horn County, MT 66 km (41 mi) ESE of here earthquakes near Big Horn County
Powder River County, MT 97 km (60 mi) WSW of here earthquakes near Powder River County
Rosebud County, MT 113 km (70 mi) S of here earthquakes near Rosebud County
Big Horn County, WY 121 km (75 mi) NE of here earthquakes near Big Horn County
Treasure County, MT 126 km (78 mi) SSE of here earthquakes near Treasure County

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

Aftershocks so far

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

  1. 2.8 35 km WSW of Birney, Montana
  2. 3.2 34 km WSW of Birney, Montana
  3. 2.6 Eastern Montana
  4. 2.5 24 km NNE of Sheridan, Wyoming
  5. 3.5 23 km NNE of Sheridan, Wyoming
  6. 3.1 26 km SW of Birney, Montana
  7. 3.3 Eastern Montana
  8. 3.1 33 km NE of Ranchester, Wyoming
  9. 2.8 24 km WSW of Birney, Montana
  10. 3.3 30 km WSW of Birney, Montana
  11. 2.8 26 km WSW of Birney, Montana
  12. 3.1 29 km NE of Ranchester, Wyoming
  13. 3.5 30 km WSW of Birney, Montana
  14. 3.3 23 km ESE of Lodge Grass, Montana
  15. 3.3 32 km SW of Birney, Montana

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.