QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7ml

14 km NNW of Winston, Montana

· 13 km deep · released about 9.3 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Broadwater County 34 kmJefferson County 60 kmMeagher County 60 kmLewis and Clark County 77 kmCascade County 84 kmPowell County 97 kmSilver Bow County 107 kmJudith Basin County 117 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 1.7 (ml)
Depth
13 km below the surface
Felt
no reports yet
Nearest
Broadwater County, 34 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 462 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 9.3 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,100,000× the energy of this one
  3. Around the size people start to feel M 3.0 100× the energy of this one
  4. This earthquake M 1.7 about 9.3 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 46.6023, -111.7085. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Broadwater County, MT 34 km (21 mi) NNW of here earthquakes near Broadwater County
Jefferson County, MT 60 km (37 mi) NNE of here earthquakes near Jefferson County
Meagher County, MT 60 km (37 mi) W of here earthquakes near Meagher County
Lewis and Clark County, MT 77 km (48 mi) SE of here earthquakes near Lewis and Clark County
Cascade County, MT 84 km (52 mi) SSW of here earthquakes near Cascade County
Powell County, MT 97 km (60 mi) ESE of here earthquakes near Powell County

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

Aftershocks so far

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

  1. 1.5 16 km NE of Helena Valley Northwest, Montana
  2. 1.6 14 km SSE of Craig, Montana
  3. 1.7 8 km W of Townsend, Montana
  4. 2.4 21 km SSE of Craig, Montana
  5. 1.6 9 km W of Townsend, Montana
  6. 1.5 9 km WSW of Townsend, Montana
  7. 1.5 1 km SSE of South Hills, Montana
  8. 1.7 0 km NNW of South Hills, Montana
  9. 2.0 32 km ENE of Helena Valley Northeast, Montana
  10. 2.0 20 km NNE of Helena Valley Northeast, Montana
  11. 1.5 31 km ENE of Helena Valley Northeast, Montana
  12. 1.9 1 km SSE of South Hills, Montana
  13. 2.4 2 km ESE of Clancy, Montana
  14. 1.9 9 km W of Townsend, Montana
  15. 1.6 3 km NNW of Townsend, 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.