QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1ml

20 km E of Finley Point, Montana

· 11 km deep · released about 43 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lake County 24 kmFlathead County 67 kmMissoula County 78 kmSanders County 104 kmTeton County 113 kmPowell County 117 kmMineral 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 2.1 (ml)
Depth
11 km below the surface
Felt
no reports yet
Nearest
Lake County, 24 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 540 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 43 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 350,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 250,000× the energy of this one
  3. Around the size people start to feel M 3.0 22× the energy of this one
  4. This earthquake M 2.1 about 43 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 47.7220, -113.7885. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lake County, MT 24 km (15 mi) ENE of here earthquakes near Lake County
Flathead County, MT 67 km (41 mi) SSE of here earthquakes near Flathead County
Missoula County, MT 78 km (48 mi) N of here earthquakes near Missoula County
Sanders County, MT 104 km (65 mi) E of here earthquakes near Sanders County
Teton County, MT 113 km (70 mi) W of here earthquakes near Teton County
Powell County, MT 117 km (73 mi) NNW of here earthquakes near Powell County

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

Aftershocks so far

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

  1. 0.9 9 km WSW of Condon, Montana
  2. 1.9 18 km E of Saint Ignatius, Montana
  3. 2.4 9 km SSW of Bear Dance, Montana
  4. 1.6 1 km SSW of Dayton, Montana
  5. 1.8 17 km SSE of Swan Lake, Montana
  6. 2.6 13 km ESE of Kicking Horse, Montana
  7. 2.0 15 km ENE of Ronan, Montana
  8. 1.7 20 km E of Finley Point, Montana
  9. 1.6 20 km E of Finley Point, Montana
  10. 1.6 20 km E of Finley Point, 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.