QuakeIndex

mining explosion · reviewed by a seismologist

M 2.9ml

Earthquake near Colstrip, MT

USGS: 5 km NNE of Colstrip, Montana

11:54 am MDT, Apr 8, 2022 · · 0.0 km deep · released about 680 lb of TNT

Every earthquake near Colstrip Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Rosebud County 28 kmTreasure County 62 kmCuster County 89 kmBig Horn County 92 kmPowder River County 99 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
11:54 am MDT on 8 April 2022 ()
Where
5 km (3 mi) NNE of Colstrip, MT · earthquakes near Colstrip
Magnitude
M 2.9 (ml)
Depth
0.0 km below the surface
Felt
no reports yet
Nearest
Rosebud County, 28 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1574 days ago

A magnitude 2.9 earthquake was recorded 5 km (3 mi) NNE of Colstrip, MT, at 11:54 am MDT on 8 April 2022 (17:54 UTC). 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 680 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 22,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 16,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.4× the energy of this one
  4. This earthquake M 2.9 about 680 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 45.9289, -106.5962. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Rosebud County, MT 28 km (17 mi) NNW earthquakes near Rosebud County
Treasure County, MT 62 km (39 mi) WNW earthquakes near Treasure County
Custer County, MT 89 km (55 mi) ENE earthquakes near Custer County
Big Horn County, MT 92 km (57 mi) SW earthquakes near Big Horn County
Powder River County, MT 99 km (62 mi) SE earthquakes near Powder River County
Prairie County, MT 129 km (80 mi) NE earthquakes near Prairie County

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

Aftershocks so far

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

  1. 3.0 18 km WSW of Colstrip, Montana
  2. 3.0 9 km WSW of Colstrip, Montana
  3. 2.8 13 km W of Colstrip, Montana
  4. 3.2 12 km NW of Colstrip, Montana
  5. 3.0 14 km W of Colstrip, Montana
  6. 3.2 19 km N of Colstrip, Montana
  7. 3.0 16 km W of Colstrip, Montana
  8. 3.1 11 km SW of Colstrip, Montana
  9. 3.2 17 km SW of Colstrip, Montana
  10. 3.3 12 km SW of Colstrip, Montana
  11. 2.9 10 km SSE of Colstrip, Montana
  12. 3.3 15 km SE of Colstrip, Montana
  13. 2.9 13 km NNW of Muddy, Montana
  14. 2.9 10 km WSW of Colstrip, Montana
  15. 3.2 8 km NNE of Colstrip, 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.