QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

17 km SSW of Condon, Montana

· 21 km deep · released about 17 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lake County 37 kmMissoula County 40 kmPowell County 88 kmMineral County 102 kmFlathead County 104 kmLewis and Clark County 110 kmSanders County 113 kmGranite County 113 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 1.8 (ml)
Depth
21 km below the surface
Felt
no reports yet
Nearest
Lake County, 37 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1108 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 17 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 900,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 640,000× the energy of this one
  3. Around the size people start to feel M 3.0 57× the energy of this one
  4. This earthquake M 1.8 about 17 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 47.3803, -113.7858. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lake County, MT 37 km (23 mi) SE of here earthquakes near Lake County
Missoula County, MT 40 km (25 mi) NNE of here earthquakes near Missoula County
Powell County, MT 88 km (55 mi) NW of here earthquakes near Powell County
Mineral County, MT 102 km (63 mi) ENE of here earthquakes near Mineral County
Flathead County, MT 104 km (64 mi) S of here earthquakes near Flathead County
Lewis and Clark County, MT 110 km (68 mi) WNW of here earthquakes near Lewis and Clark County

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

Aftershocks so far

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

  1. 0.9 9 km WSW of Condon, Montana
  2. 3.2 3 km NE of Seeley Lake, Montana
  3. 1.9 15 km N of Seeley Lake, Montana
  4. 1.9 18 km E of Saint Ignatius, 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. 2.1 5 km WNW of Saint Ignatius, Montana
  9. 1.7 20 km E of Finley Point, Montana
  10. 1.6 20 km E of Finley Point, Montana
  11. 1.6 20 km E of Finley Point, Montana
  12. 2.1 20 km E of Finley Point, Montana
  13. 1.8 17 km E of Condon, Montana
  14. 1.7 19 km E of Finley Point, Montana
  15. 1.6 16 km NNE of Condon, 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.