QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5ml

10 km ENE of Townsend, Montana

· 5.0 km deep · released about 170 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Broadwater County 8 kmMeagher County 44 kmJefferson County 57 kmGallatin County 97 kmCascade County 105 kmSilver Bow County 110 kmJudith Basin County 112 kmLewis and Clark County 112 kmWheatland County 120 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 2.5 (ml)
Depth
5.0 km below the surface
Felt
no reports yet
Nearest
Broadwater County, 8 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2649 days ago

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

How big was it?

This earthquake released about 170 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 89,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 63,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.6× the energy of this one
  4. This earthquake M 2.5 about 170 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 46.3697, -111.4068. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Broadwater County, MT 8 km (5 mi) ENE of here earthquakes near Broadwater County
Meagher County, MT 44 km (27 mi) WSW of here earthquakes near Meagher County
Jefferson County, MT 57 km (35 mi) ENE of here earthquakes near Jefferson County
Gallatin County, MT 97 km (60 mi) N of here earthquakes near Gallatin County
Cascade County, MT 105 km (65 mi) S of here earthquakes near Cascade County
Silver Bow County, MT 110 km (68 mi) ENE of here earthquakes near Silver Bow County

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

Aftershocks so far

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

  1. 1.6 6 km W of Townsend, Montana
  2. 1.8 4 km S of Radersburg, Montana
  3. 2.1 6 km ENE of Toston, Montana
  4. 1.7 5 km W of Townsend, Montana
  5. 1.5 4 km WNW of Townsend, Montana
  6. 1.7 6 km NNE of Logan, Montana
  7. 2.3 11 km ENE of Toston, Montana
  8. 2.0 7 km ENE of Toston, Montana
  9. 1.9 10 km SE of Ponderosa Pines, Montana
  10. 2.1 10 km SE of Ponderosa Pines, Montana
  11. 1.5 6 km W of Townsend, Montana
  12. 1.7 3 km SSW of Radersburg, Montana
  13. 1.7 9 km ENE of Townsend, Montana
  14. 1.6 7 km NNW of Logan, Montana
  15. 1.6 6 km WSW of Townsend, 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.