QuakeIndex

Earthquake · reviewed by a seismologist

M 2.3md

6 km N of Saint Ignatius, Montana

· -2.4 km deep · released about 72 lb of TNT

10 km30 km60 km120 km N Lake County 29 kmMissoula County 42 kmMineral County 80 kmSanders County 92 kmFlathead County 102 kmPowell County 106 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 2.3 (md)
Depth
-2.4 km below the surface
Felt
no reports yet
Nearest
Lake County, 29 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2368 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 72 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.3 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 210,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 150,000× the energy of this one
  3. Around the size people start to feel M 3.0 13× the energy of this one
  4. This earthquake M 2.3 about 72 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 47.3780, -114.0940. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lake County, MT 29 km (18 mi) S of here earthquakes near Lake County
Missoula County, MT 42 km (26 mi) NNW of here earthquakes near Missoula County
Mineral County, MT 80 km (50 mi) ENE of here earthquakes near Mineral County
Sanders County, MT 92 km (57 mi) ESE of here earthquakes near Sanders County
Flathead County, MT 102 km (63 mi) S of here earthquakes near Flathead County
Powell County, MT 106 km (66 mi) NW of here earthquakes near Powell 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. 2.2 2 km NE of Alberton, Montana
  2. 1.7 4 km WNW of Wye, Montana
  3. 2.6 13 km ESE of Kicking Horse, Montana
  4. 2.0 15 km ENE of Ronan, Montana
  5. 2.1 5 km WNW of Saint Ignatius, Montana
  6. 1.7 20 km E of Finley Point, Montana
  7. 1.6 20 km E of Finley Point, Montana
  8. 1.6 20 km E of Finley Point, Montana
  9. 2.1 20 km E of Finley Point, Montana
  10. 1.7 19 km E of Finley Point, Montana
  11. 1.6 16 km NNE of Condon, Montana
  12. 1.8 14 km WNW of Condon, Montana
  13. 1.5 12 km SW of Seeley Lake, Montana
  14. 1.6 16 km WSW of Kerr, Montana
  15. 1.5 5 km NE of Saint Ignatius, 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.