QuakeIndex

Earthquake · reviewed by a seismologist

M 3.3ml

16 km S of Whitehall, Montana

· 6.8 km deep · released about 1.5 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Jefferson County 45 kmSilver Bow County 46 kmMadison County 48 kmGallatin County 78 kmBroadwater County 83 kmDeer Lodge County 89 kmBeaverhead County 89 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 3.3 (ml)
Depth
6.8 km below the surface
Felt
2 reports · strongest reported intensity III
Nearest
Jefferson County, 45 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1962 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 1.5 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.3 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 110,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 5,100× the energy of this one
  3. Magna, Utah 2020 M 5.7 3,600× the energy of this one
  4. This earthquake M 3.3 about 1.5 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 3.1× more

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 45.7265, -112.1242. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Jefferson County, MT 45 km (28 mi) S of here earthquakes near Jefferson County
Silver Bow County, MT 46 km (28 mi) ESE of here earthquakes near Silver Bow County
Madison County, MT 48 km (30 mi) NNW of here earthquakes near Madison County
Gallatin County, MT 78 km (49 mi) WNW of here earthquakes near Gallatin County
Broadwater County, MT 83 km (51 mi) SW of here earthquakes near Broadwater County
Deer Lodge County, MT 89 km (55 mi) ESE of here earthquakes near Deer Lodge County

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

Aftershocks so far

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

  1. 2.1 5 km E of Butte, Montana
  2. 1.6 8 km SW of Pony, Montana
  3. 1.8 5 km E of Butte, Montana
  4. 1.7 4 km ENE of Butte, Montana
  5. 1.9 4 km ENE of Butte, Montana
  6. 2.1 6 km ENE of Butte, Montana
  7. 1.7 4 km E of Butte, Montana
  8. 1.6 5 km ENE of Butte, Montana
  9. 1.9 5 km E of Butte, Montana
  10. 1.6 4 km E of Butte, Montana
  11. 2.2 5 km E of Butte, Montana
  12. 1.9 7 km WNW of Ennis, Montana
  13. 1.9 5 km E of Butte, Montana
  14. 2.5 15 km S of Whitehall, Montana
  15. 1.8 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 11 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.