QuakeIndex

Earthquake · reviewed by a seismologist

M 2.2ml

38 km WSW of Augusta, Montana

· 22 km deep · released about 52 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lewis and Clark County 47 kmPowell County 61 kmTeton County 65 kmMissoula County 87 kmLake County 95 kmPondera County 105 kmCascade County 115 kmGranite County 118 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
22 km below the surface
Felt
no reports yet
Nearest
Lewis and Clark County, 47 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2889 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 52 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 5.8 290,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 200,000× the energy of this one
  3. Around the size people start to feel M 3.0 18× the energy of this one
  4. This earthquake M 2.2 about 52 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 47.3873, -112.8727. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lewis and Clark County, MT 47 km (29 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 65 km (41 mi) SW of here earthquakes near Teton County
Missoula County, MT 87 km (54 mi) ENE of here earthquakes near Missoula County
Lake County, MT 95 km (59 mi) ESE of here earthquakes near Lake County
Pondera County, MT 105 km (66 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

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

  1. 1.8 27 km W of Augusta, Montana
  2. 2.4 Western Montana
  3. 1.6 27 km W of Augusta, Montana
  4. 1.6 24 km W of Augusta, Montana
  5. 1.6 3 km WNW of Lincoln, Montana
  6. 2.3 19 km NNE of Seeley Lake, Montana
  7. 2.8 6 km WNW of Lincoln, Montana
  8. 2.3 Western Montana
  9. 1.8 11 km W of Lincoln, Montana
  10. 2.3 13 km WNW of Lincoln, Montana
  11. 2.5 18 km N of Ovando, Montana
  12. 2.1 18 km WNW of Lincoln, Montana
  13. 2.5 8 km NW of Lincoln, Montana
  14. 2.7 19 km ENE of Seeley Lake, Montana
  15. 2.4 26 km ENE of Seeley Lake, 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.