QuakeIndex

Earthquake · reviewed by a seismologist

M 2.4ml

27 km E of Swan Lake, Montana

· 8.2 km deep · released about 120 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lake County 55 kmFlathead County 59 kmTeton County 90 kmGlacier County 94 kmPondera County 99 kmMissoula County 105 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 2.4 (ml)
Depth
8.2 km below the surface
Felt
no reports yet
Nearest
Lake County, 55 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 758 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 120 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 130,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 89,000× the energy of this one
  3. Around the size people start to feel M 3.0 7.9× the energy of this one
  4. This earthquake M 2.4 about 120 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 47.9277, -113.4761. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lake County, MT 55 km (34 mi) NE of here earthquakes near Lake County
Flathead County, MT 59 km (37 mi) SE of here earthquakes near Flathead County
Teton County, MT 90 km (56 mi) W of here earthquakes near Teton County
Glacier County, MT 94 km (58 mi) SSW of here earthquakes near Glacier County
Pondera County, MT 99 km (62 mi) WSW of here earthquakes near Pondera County
Missoula County, MT 105 km (65 mi) NNE of here earthquakes near Missoula County

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

Aftershocks so far

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

  1. 1.8 17 km SSE of Swan Lake, Montana
  2. 1.6 40 km ENE of Condon, Montana
  3. 1.7 20 km E of Finley Point, Montana
  4. 1.6 20 km E of Finley Point, Montana
  5. 1.6 20 km E of Finley Point, Montana
  6. 2.1 20 km E of Finley Point, Montana
  7. 1.8 17 km E of Condon, Montana
  8. 1.7 19 km E of Finley Point, Montana
  9. 1.6 16 km NNE of Condon, Montana
  10. 1.7 30 km ESE of Martin City, Montana
  11. 2.1 27 km E of Swan Lake, Montana
  12. 2.5 24 km E of Swan 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.