QuakeIndex

Earthquake · reviewed by a seismologist

M 3.2ml

12 km NNW of Avon, Montana

· 12 km deep · released about 1,900 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Powell County 25 kmLewis and Clark County 54 kmGranite County 65 kmDeer Lodge County 75 kmJefferson County 79 kmSilver Bow County 88 kmMissoula County 99 kmBroadwater County 99 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 3.2 (ml)
Depth
12 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Powell County, 25 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 207 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 1 person has reported feeling it to USGS.

How big was it?

This earthquake released about 1,900 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 180,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 7,900× the energy of this one
  3. Magna, Utah 2020 M 5.7 5,600× the energy of this one
  4. This earthquake M 3.2 about 1,900 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 2× 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 46.6877, -112.6895. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Powell County, MT 25 km (16 mi) SE of here earthquakes near Powell County
Lewis and Clark County, MT 54 km (33 mi) SSW of here earthquakes near Lewis and Clark County
Granite County, MT 65 km (40 mi) ENE of here earthquakes near Granite County
Deer Lodge County, MT 75 km (46 mi) NNE of here earthquakes near Deer Lodge County
Jefferson County, MT 79 km (49 mi) NW of here earthquakes near Jefferson County
Silver Bow County, MT 88 km (55 mi) N 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

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

  1. 1.7 8 km S of Marysville, Montana
  2. 1.7 13 km SE of Lincoln, Montana
  3. 1.7 16 km W of Lincoln, Montana
  4. 2.4 7 km SSE of Lincoln, Montana
  5. 2.0 7 km SSE of Lincoln, Montana
  6. 1.5 14 km SE of Lincoln, Montana
  7. 1.8 19 km S of Lincoln, Montana
  8. 1.9 7 km S of Lincoln, Montana
  9. 1.8 19 km NNW of Avon, Montana
  10. 2.8 19 km S of Lincoln, Montana
  11. 1.6 14 km ESE of Lincoln, Montana
  12. 2.2 19 km S of Lincoln, Montana
  13. 1.6 19 km S of Lincoln, Montana
  14. 1.7 19 km S of Lincoln, Montana
  15. 1.8 19 km NNW of Avon, 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 5.8 on 2017-07-06 — it released about 7,900 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.