QuakeIndex

Earthquake · reviewed by a seismologist

M 2.3ml

38 km WNW of Augusta, Montana

· 18 km deep · released about 85 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Teton County 48 kmLewis and Clark County 66 kmPondera County 83 kmPowell County 87 kmLake County 92 kmMissoula County 102 kmFlathead County 116 kmCascade County 119 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 (ml)
Depth
18 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Teton County, 48 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3340 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 1 person has reported feeling it to USGS.

How big was it?

This earthquake released about 85 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 5.8 180,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 130,000× the energy of this one
  3. Around the size people start to feel M 3.0 11× the energy of this one
  4. This earthquake M 2.3 about 85 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 47.6230, -112.8607. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Teton County, MT 48 km (30 mi) WSW of here earthquakes near Teton County
Lewis and Clark County, MT 66 km (41 mi) NNW of here earthquakes near Lewis and Clark County
Pondera County, MT 83 km (51 mi) SW of here earthquakes near Pondera County
Powell County, MT 87 km (54 mi) N of here earthquakes near Powell County
Lake County, MT 92 km (57 mi) E of here earthquakes near Lake County
Missoula County, MT 102 km (63 mi) NE of here earthquakes near Missoula County

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

Aftershocks so far

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

  1. 2.2 36 km NE of Seeley Lake, Montana
  2. 1.5 36 km NE of Seeley Lake, Montana
  3. 1.9 36 km NE of Seeley Lake, Montana
  4. 2.2 36 km NE of Seeley Lake, Montana
  5. 2.2 47 km WNW of Augusta, Montana
  6. 2.3 25 km ENE of Seeley Lake, Montana
  7. 1.8 22 km ENE of Seeley Lake, Montana
  8. 2.4 32 km WSW of Augusta, Montana
  9. 1.6 38 km WSW of Augusta, Montana
  10. 1.8 27 km W of Augusta, Montana
  11. 2.4 Western Montana
  12. 1.6 27 km W of Augusta, Montana
  13. 1.6 24 km W of Augusta, Montana
  14. 2.3 Western Montana
  15. 2.7 19 km ENE of Seeley 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.