QuakeIndex

mine collapse · reviewed by a seismologist

M 2.6ml

9 km S of Troy, Montana

· 1.0 km deep · released about 240 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lincoln County 35 kmBonner County 56 kmBoundary County 65 kmSanders County 87 kmKootenai County 100 kmPend Oreille County 102 kmShoshone County 115 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 2.6 (ml)
Depth
1.0 km below the surface
Felt
no reports yet
Nearest
Lincoln County, 35 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2656 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

USGS catalogues this as mine collapse, not an earthquake.

How big was it?

This earthquake released about 240 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 63,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 45,000× the energy of this one
  3. Around the size people start to feel M 3.0 4× the energy of this one
  4. This earthquake M 2.6 about 240 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 48.3831, -115.8705. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lincoln County, MT 35 km (22 mi) WSW of here earthquakes near Lincoln County
Bonner County, ID 56 km (35 mi) E of here earthquakes near Bonner County
Boundary County, ID 65 km (40 mi) SE of here earthquakes near Boundary County
Sanders County, MT 87 km (54 mi) NW of here earthquakes near Sanders County
Kootenai County, ID 100 km (62 mi) NE of here earthquakes near Kootenai County
Pend Oreille County, WA 102 km (63 mi) E of here earthquakes near Pend Oreille County

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

Aftershocks so far

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

  1. 3.1 20 km N of Heron, Montana
  2. 2.1 7 km WSW of Clark Fork, Idaho
  3. 1.8 13 km SSW of East Hope, Idaho
  4. 1.5 11 km SSW of East Hope, Idaho
  5. 2.5 10 km SSW of East Hope, Idaho
  6. 2.6 7 km W of Clark Fork, Idaho
  7. 1.9 19 km NE of Troy, Montana
  8. 1.8 15 km SE of Sylvanite, Montana
  9. 1.6 13 km SSW of East Hope, Idaho
  10. 2.4 23 km ENE of Noxon, Montana
  11. 2.0 13 km WSW of Libby, Montana
  12. 1.6 7 km S of Moyie Springs, Idaho
  13. 1.6 10 km SSW of East Hope, Idaho
  14. 1.6 6 km NW of Libby, 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.