QuakeIndex

mining explosion · reviewed by a seismologist

M 3.3ml

23 km ESE of Lodge Grass, Montana

· 0.0 km deep · released about 1.3 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Big Horn County 39 kmSheridan County 53 kmBig Horn County 107 kmRosebud County 110 kmTreasure County 112 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 3.3 (ml)
Depth
0.0 km below the surface
Felt
no reports yet
Nearest
Big Horn County, 39 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1408 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 1.3 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.3 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 130,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 5,600× the energy of this one
  3. Magna, Utah 2020 M 5.7 4,000× the energy of this one
  4. This earthquake M 3.3 about 1.3 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 2.8× more

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 45.2320, -107.0818. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Big Horn County, MT 39 km (24 mi) ESE of here earthquakes near Big Horn County
Sheridan County, WY 53 km (33 mi) NNW of here earthquakes near Sheridan County
Big Horn County, WY 107 km (66 mi) NE of here earthquakes near Big Horn County
Rosebud County, MT 110 km (68 mi) SSW of here earthquakes near Rosebud County
Treasure County, MT 112 km (69 mi) S of here earthquakes near Treasure County
Powder River County, MT 121 km (75 mi) W of here earthquakes near Powder River 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. 3.1 28 km NE of Ranchester, Wyoming
  2. 2.6 17 km NE of Ranchester, Wyoming
  3. 3.5 31 km NE of Ranchester, Wyoming
  4. 2.8 33 km NNE of Sheridan, Wyoming
  5. 3.5 33 km NE of Ranchester, Wyoming
  6. 2.9 28 km ENE of Ranchester, Wyoming
  7. 2.9 29 km NNE of Sheridan, Wyoming
  8. 3.0 31 km NNE of Sheridan, Wyoming
  9. 3.2 28 km NE of Ranchester, Wyoming
  10. 3.3 31 km NE of Ranchester, Wyoming
  11. 2.6 33 km NE of Ranchester, Wyoming
  12. 3.2 29 km NE of Ranchester, Wyoming
  13. 3.5 27 km NE of Ranchester, Wyoming
  14. 3.5 24 km NE of Ranchester, Wyoming
  15. 2.8 28 km NE of Ranchester, 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.