QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

18 km NNE of Challis, Idaho

· 5.3 km deep · released about 14 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lemhi County 36 kmCuster County 44 kmBeaverhead County 111 kmValley 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 1.8 (ml)
Depth
5.3 km below the surface
Felt
no reports yet
Nearest
Lemhi County, 36 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1764 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 14 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 760,000× the energy of this one
  3. Around the size people start to feel M 3.0 68× the energy of this one
  4. This earthquake M 1.8 about 14 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 44.6580, -114.1372. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lemhi County, ID 36 km (22 mi) SSW of here earthquakes near Lemhi County
Custer County, ID 44 km (27 mi) NNE of here earthquakes near Custer County
Beaverhead County, MT 111 km (69 mi) WSW of here earthquakes near Beaverhead County
Valley County, ID 119 km (74 mi) E of here earthquakes near Valley County
Butte County, ID 133 km (82 mi) NW of here earthquakes near Butte County

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

Aftershocks so far

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

  1. 1.7 21 km NNW of Challis, Idaho
  2. 2.1 southern Idaho
  3. 3.4 24 km NNW of Challis, Idaho
  4. 3.2 20 km NW of Challis, Idaho
  5. 2.4 29 km WNW of Challis, Idaho
  6. 1.6 29 km WNW of Challis, Idaho
  7. 2.9 27 km WNW of Challis, Idaho
  8. 3.0 26 km WSW of Leadore, Idaho
  9. 2.7 24 km NNW of Clayton, Idaho
  10. 1.5 21 km NNW of Challis, Idaho
  11. 2.6 34 km W of Challis, Idaho
  12. 2.3 35 km W of Challis, Idaho
  13. 1.5 25 km NNW of Clayton, Idaho
  14. 2.6 18 km NW of Challis, Idaho
  15. 3.4 21 km NW of Challis, Idaho

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.