QuakeIndex

quarry blast · reviewed by a seismologist

M 1.7ml

28 km SE of Virginia City, Montana

· -2.0 km deep · released about 12 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Madison County 31 kmGallatin County 66 kmBeaverhead County 91 kmFremont County 98 kmClark County 101 kmPark County 103 kmSilver Bow County 116 kmJefferson 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 1.7 (ml)
Depth
-2.0 km below the surface
Felt
no reports yet
Nearest
Madison County, 31 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1713 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

USGS catalogues this as quarry blast, not an earthquake.

How big was it?

This earthquake released about 12 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,300,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 900,000× the energy of this one
  3. Around the size people start to feel M 3.0 80× the energy of this one
  4. This earthquake M 1.7 about 12 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 45.0820, -111.7335. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Madison County, MT 31 km (19 mi) SSE of here earthquakes near Madison County
Gallatin County, MT 66 km (41 mi) SW of here earthquakes near Gallatin County
Beaverhead County, MT 91 km (57 mi) E of here earthquakes near Beaverhead County
Fremont County, ID 98 km (61 mi) NNW of here earthquakes near Fremont County
Clark County, ID 101 km (63 mi) NNE of here earthquakes near Clark County
Park County, MT 103 km (64 mi) WSW of here earthquakes near Park County

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

Aftershocks so far

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

  1. 2.1 34 km S of Virginia City, Montana
  2. 1.5 35 km S of Virginia City, Montana
  3. 1.7 33 km S of Virginia City, Montana
  4. 2.3 40 km NE of Spencer, Idaho
  5. 1.6 17 km S of Pony, Montana
  6. 2.4 30 km WNW of Hebgen Lake Estates, Montana
  7. 2.0 9 km WNW of Hebgen Lake Estates, Montana
  8. 1.5 29 km WNW of Hebgen Lake Estates, Montana
  9. 1.6 42 km S of Alder, Montana
  10. 2.2 32 km S of Virginia City, Montana
  11. 1.5 29 km S of Ennis, Montana
  12. 1.6 23 km WNW of Hebgen Lake Estates, Montana
  13. 1.5 Idaho-Montana border region
  14. 1.8 18 km N of Ennis, Montana
  15. 1.8 53 km NNE of Spencer, Idaho

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 8,200 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.