QuakeIndex

Earthquake · reviewed by a seismologist

M 2.2ml

41 km WSW of Augusta, Montana

· 23 km deep · released about 64 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lewis and Clark County 50 kmPowell County 61 kmTeton County 68 kmMissoula County 83 kmLake County 92 kmPondera County 107 kmGranite County 117 kmCascade County 119 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 2.2 (ml)
Depth
23 km below the surface
Felt
no reports yet
Nearest
Lewis and Clark County, 50 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2858 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 64 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.2 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 230,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 170,000× the energy of this one
  3. Around the size people start to feel M 3.0 15× the energy of this one
  4. This earthquake M 2.2 about 64 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 47.3883, -112.9238. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lewis and Clark County, MT 50 km (31 mi) NW of here earthquakes near Lewis and Clark County
Powell County, MT 61 km (38 mi) N of here earthquakes near Powell County
Teton County, MT 68 km (42 mi) SW of here earthquakes near Teton County
Missoula County, MT 83 km (52 mi) ENE of here earthquakes near Missoula County
Lake County, MT 92 km (57 mi) ESE of here earthquakes near Lake County
Pondera County, MT 107 km (67 mi) SSW of here earthquakes near Pondera County

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

Aftershocks so far

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

  1. 2.4 32 km WSW of Augusta, Montana
  2. 1.6 38 km WSW of Augusta, Montana
  3. 1.8 27 km W of Augusta, Montana
  4. 2.4 Western Montana
  5. 1.6 27 km W of Augusta, Montana
  6. 1.6 24 km W of Augusta, Montana
  7. 1.6 3 km WNW of Lincoln, Montana
  8. 2.3 19 km NNE of Seeley Lake, Montana
  9. 2.8 6 km WNW of Lincoln, Montana
  10. 2.3 Western Montana
  11. 1.8 11 km W of Lincoln, Montana
  12. 2.3 13 km WNW of Lincoln, Montana
  13. 2.5 18 km N of Ovando, Montana
  14. 2.1 18 km WNW of Lincoln, Montana
  15. 2.5 8 km NW of Lincoln, 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.