QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1ml

34 km S of Virginia City, Montana

· 5.6 km deep · released about 44 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Madison County 38 kmBeaverhead County 76 kmClark County 84 kmGallatin County 86 kmFremont County 93 kmSilver Bow County 116 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 2.1 (ml)
Depth
5.6 km below the surface
Felt
no reports yet
Nearest
Madison County, 38 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 898 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 44 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 340,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 240,000× the energy of this one
  3. Around the size people start to feel M 3.0 22× the energy of this one
  4. This earthquake M 2.1 about 44 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 44.9840, -111.9502. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Madison County, MT 38 km (24 mi) S of here earthquakes near Madison County
Beaverhead County, MT 76 km (47 mi) ESE of here earthquakes near Beaverhead County
Clark County, ID 84 km (52 mi) NNE of here earthquakes near Clark County
Gallatin County, MT 86 km (53 mi) SW of here earthquakes near Gallatin County
Fremont County, ID 93 km (58 mi) NNW of here earthquakes near Fremont County
Silver Bow County, MT 116 km (72 mi) SSE of here earthquakes near Silver Bow County

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

Aftershocks so far

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

  1. 1.9 21 km S of Ennis, Montana
  2. 1.6 28 km SE of Virginia City, Montana
  3. 2.3 47 km NW of Island Park, Idaho
  4. 1.6 31 km SSE of Virginia City, Montana
  5. 1.8 40 km NNE of Spencer, Idaho
  6. 2.0 11 km S of Ennis, Montana
  7. 1.7 22 km WNW of Hebgen Lake Estates, Montana
  8. 1.6 43 km W of Hebgen Lake Estates, Montana
  9. 1.5 28 km S of Ennis, Montana
  10. 1.6 31 km NNE of Spencer, Idaho
  11. 1.7 29 km WNW of Hebgen Lake Estates, Montana
  12. 1.5 21 km W of Hebgen Lake Estates, Montana
  13. 1.6 40 km NE of Spencer, Idaho
  14. 1.9 31 km SSE of Virginia City, Montana
  15. 1.6 29 km SSE of Virginia City, 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 2,200 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.