QuakeIndex

Earthquake · reviewed by a seismologist

M 2.7ml

18 km W of Whitehall, Montana

· 12 km deep · released about 340 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Silver Bow County 25 kmJefferson County 36 kmDeer Lodge County 67 kmMadison County 68 kmBroadwater County 83 kmBeaverhead County 92 kmGallatin County 99 kmGranite County 103 kmPowell County 118 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 2.7 (ml)
Depth
12 km below the surface
Felt
11 reports · strongest reported intensity II
Nearest
Silver Bow County, 25 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 351 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 11 people have reported feeling it to USGS.

How big was it?

This earthquake released about 340 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 45,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 32,000× the energy of this one
  3. Around the size people start to feel M 3.0 2.8× the energy of this one
  4. This earthquake M 2.7 about 340 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 45.8650, -112.3373. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Silver Bow County, MT 25 km (16 mi) E of here earthquakes near Silver Bow County
Jefferson County, MT 36 km (22 mi) SW of here earthquakes near Jefferson County
Deer Lodge County, MT 67 km (42 mi) ESE of here earthquakes near Deer Lodge County
Madison County, MT 68 km (43 mi) NNW of here earthquakes near Madison County
Broadwater County, MT 83 km (51 mi) SW of here earthquakes near Broadwater County
Beaverhead County, MT 92 km (57 mi) NNE of here earthquakes near Beaverhead County

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

Aftershocks so far

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

  1. 1.8 5 km E of Butte, Montana
  2. 1.8 5 km ESE of Walkerville, Montana
  3. 1.8 5 km E of Butte, Montana
  4. 2.0 2 km NNW of Pony, Montana
  5. 1.8 6 km E of Walkerville, Montana
  6. 1.5 4 km E of Butte, Montana
  7. 1.9 5 km E of Butte, Montana
  8. 1.6 5 km E of Butte, Montana
  9. 2.3 14 km NNE of Twin Bridges, Montana
  10. 2.9 14 km NNE of Twin Bridges, Montana
  11. 1.8 14 km NNE of Twin Bridges, Montana
  12. 3.0 16 km ESE of Butte, Montana
  13. 1.6 5 km E of Butte, Montana
  14. 1.7 4 km E of Butte, Montana
  15. 1.5 4 km E of Butte, 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 4.0 on 2016-09-03 — it released about 99 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.