QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5ml

23 km SE of Virginia City, Montana

· 8.1 km deep · released about 170 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Madison County 25 kmGallatin County 64 kmBeaverhead County 88 kmPark County 103 kmFremont County 104 kmClark County 104 kmSilver Bow County 110 kmJefferson 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 2.5 (ml)
Depth
8.1 km below the surface
Felt
2 reports · strongest reported intensity II
Nearest
Madison County, 25 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1828 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 2 people have reported feeling it to USGS.

How big was it?

This earthquake released about 170 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 89,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 63,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.6× the energy of this one
  4. This earthquake M 2.5 about 170 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 45.1274, -111.7679. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Madison County, MT 25 km (15 mi) SSE of here earthquakes near Madison County
Gallatin County, MT 64 km (40 mi) SW of here earthquakes near Gallatin County
Beaverhead County, MT 88 km (55 mi) E of here earthquakes near Beaverhead County
Park County, MT 103 km (64 mi) WSW of here earthquakes near Park County
Fremont County, ID 104 km (64 mi) NNW of here earthquakes near Fremont County
Clark County, ID 104 km (65 mi) NNE of here earthquakes near Clark County

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

Aftershocks so far

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

  1. 1.5 29 km S of Ennis, Montana
  2. 1.6 23 km WNW of Hebgen Lake Estates, Montana
  3. 1.5 Idaho-Montana border region
  4. 1.8 18 km N of Ennis, Montana
  5. 1.8 53 km NNE of Spencer, Idaho
  6. 1.9 37 km SW of Big Sky, Montana
  7. 1.7 16 km N of Big Sky, Montana
  8. 2.5 46 km NW of Island Park, Idaho
  9. 1.6 28 km SE of Virginia City, Montana
  10. 1.8 41 km W of Hebgen Lake Estates, Montana
  11. 1.7 28 km S of Ennis, Montana
  12. 2.1 17 km NNE of Ennis, Montana
  13. 3.1 45 km NW of Island Park, Idaho
  14. 2.1 45 km NW of Island Park, Idaho
  15. 1.5 23 km WNW of Hebgen Lake Estates, 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.3 on 2016-06-13 — it released about 580 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.