QuakeIndex

Earthquake · reviewed by a seismologist

M 3.9mwr

28 km W of Hebgen Lake Estates, Montana

· 12 km deep · released about 11 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Fremont County 65 kmMadison County 65 kmGallatin County 85 kmClark County 86 kmPark County 108 kmBeaverhead County 112 kmMadison County 113 kmTeton 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 3.9 (mwr)
Depth
12 km below the surface
Felt
26 reports · strongest reported intensity IV
Measured shaking
intensity IV (ShakeMap)
Nearest
Fremont County, 65 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2322 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 26 people have reported feeling it to USGS.

How big was it?

This earthquake released about 11 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.9 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 16,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 710× the energy of this one
  3. Magna, Utah 2020 M 5.7 500× the energy of this one
  4. This earthquake M 3.9 about 11 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 22× 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 44.8003, -111.5449. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Fremont County, ID 65 km (40 mi) N of here earthquakes near Fremont County
Madison County, MT 65 km (40 mi) SSE of here earthquakes near Madison County
Gallatin County, MT 85 km (53 mi) SSW of here earthquakes near Gallatin County
Clark County, ID 86 km (53 mi) NE of here earthquakes near Clark County
Park County, MT 108 km (67 mi) SW of here earthquakes near Park County
Beaverhead County, MT 112 km (70 mi) ESE of here earthquakes near Beaverhead County

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

Aftershocks so far

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

  1. 1.6 32 km S of Ennis, Montana
  2. 1.6 23 km WNW of Hebgen Lake Estates, Montana
  3. 2.0 22 km WNW of Hebgen Lake Estates, Montana
  4. 1.8 46 km NNE of Spencer, Idaho
  5. 2.2 1 km SSW of West Yellowstone, Montana
  6. 2.1 1 km SSW of West Yellowstone, Montana
  7. 2.3 1 km SW of West Yellowstone, Montana
  8. 1.5 8 km ENE of Hebgen Lake Estates, Montana
  9. 1.6 8 km E of Hebgen Lake Estates, Montana
  10. 1.5 29 km S of Ennis, Montana
  11. 1.9 22 km WNW of Hebgen Lake Estates, Montana
  12. 1.7 7 km E of Hebgen Lake Estates, Montana
  13. 1.6 14 km SSE of West Yellowstone, Montana
  14. 2.6 13 km E of Hebgen Lake Estates, Montana
  15. 1.5 26 km W of Hebgen Lake Estates, 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 4.4 on 2017-06-16 — it released about 4.9 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.