QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6ml

13 km S of Ennis, Montana

· 5.0 km deep · released about 9 lb of TNT

10 km30 km60 km120 km N Madison County 19 kmGallatin County 54 kmBeaverhead County 93 kmPark County 96 kmJefferson County 103 kmSilver Bow County 104 kmFremont County 114 kmClark County 116 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 1.6 (ml)
Depth
5.0 km below the surface
Felt
no reports yet
Nearest
Madison County, 19 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1172 days ago

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

How big was it?

This earthquake released about 9 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,700,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,200,000× the energy of this one
  3. Around the size people start to feel M 3.0 110× the energy of this one
  4. This earthquake M 1.6 about 9 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 45.2298, -111.7155. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Madison County, MT 19 km (12 mi) SE of here earthquakes near Madison County
Gallatin County, MT 54 km (33 mi) SW of here earthquakes near Gallatin County
Beaverhead County, MT 93 km (58 mi) E of here earthquakes near Beaverhead County
Park County, MT 96 km (60 mi) WSW of here earthquakes near Park County
Jefferson County, MT 103 km (64 mi) SSE of here earthquakes near Jefferson County
Silver Bow County, MT 104 km (65 mi) SE 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

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

  1. 1.7 29 km WNW of Hebgen Lake Estates, Montana
  2. 1.9 31 km SSE of Virginia City, Montana
  3. 1.6 29 km SSE of Virginia City, Montana
  4. 2.4 8 km SSE of Pony, Montana
  5. 1.8 25 km WNW of Hebgen Lake Estates, Montana
  6. 2.1 29 km WNW of Hebgen Lake Estates, Montana
  7. 1.9 33 km S of Virginia City, Montana
  8. 1.5 28 km SE of Virginia City, Montana
  9. 1.5 28 km S of Ennis, Montana
  10. 2.6 43 km WNW of Hebgen Lake Estates, Montana
  11. 1.9 43 km W of Hebgen Lake Estates, Montana
  12. 1.7 18 km WNW of Hebgen Lake Estates, Montana
  13. 2.3 18 km NW of Hebgen Lake Estates, Montana
  14. 2.0 7 km SE of Pony, Montana
  15. 1.5 29 km SE of Virginia City, 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.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.