QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

19 km E of Challis, Idaho

· 6.5 km deep · released about 15 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Custer County 32 kmLemhi County 49 kmButte County 110 kmBeaverhead County 112 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
6.5 km below the surface
Felt
no reports yet
Nearest
Custer County, 32 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1823 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 15 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 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 710,000× the energy of this one
  3. Around the size people start to feel M 3.0 63× the energy of this one
  4. This earthquake M 1.8 about 15 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 44.4925, -113.9828. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Custer County, ID 32 km (20 mi) NE of here earthquakes near Custer County
Lemhi County, ID 49 km (30 mi) S of here earthquakes near Lemhi County
Butte County, ID 110 km (69 mi) NW of here earthquakes near Butte County
Beaverhead County, MT 112 km (69 mi) SW of here earthquakes near Beaverhead County
Camas County, ID 127 km (79 mi) NNE of here earthquakes near Camas 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. 2.2 southern Idaho
  2. 2.3 32 km NNW of Challis, Idaho
  3. 2.3 32 km NNW of Challis, Idaho
  4. 2.5 33 km NNW of Challis, Idaho
  5. 2.5 33 km NNW of Challis, Idaho
  6. 2.0 southern Idaho
  7. 1.8 32 km NNW of Challis, Idaho
  8. 2.0 34 km NNW of Challis, Idaho
  9. 1.6 18 km NW of Challis, Idaho
  10. 1.9 34 km NW of Mackay, Idaho
  11. 2.2 24 km NW of Challis, Idaho
  12. 1.6 33 km NNW of Challis, Idaho
  13. 2.3 21 km NNW of Challis, Idaho
  14. 1.7 21 km NNW of Challis, Idaho
  15. 2.1 southern 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.