QuakeIndex

Earthquake · reviewed by a seismologist

M 3.6mwr

37 km NNW of Challis, Idaho

· 15 km deep · released about 3.8 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lemhi County 42 kmCuster County 62 kmValley County 96 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 3.6 (mwr)
Depth
15 km below the surface
Felt
20 reports · strongest reported intensity III
Measured shaking
intensity III (ShakeMap)
Nearest
Lemhi County, 42 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1075 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 20 people have reported feeling it to USGS.

How big was it?

This earthquake released about 3.8 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.6 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 45,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 2,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 1,400× the energy of this one
  4. This earthquake M 3.6 about 3.8 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 7.9× 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 44.8197, -114.3969. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lemhi County, ID 42 km (26 mi) WSW of here earthquakes near Lemhi County
Custer County, ID 62 km (38 mi) N of here earthquakes near Custer County
Valley County, ID 96 km (60 mi) E of here earthquakes near Valley County
Beaverhead County, MT 123 km (77 mi) WSW of here earthquakes near Beaverhead County
Boise County, ID 140 km (87 mi) NE of here earthquakes near Boise County
Idaho County, ID 142 km (88 mi) SE of here earthquakes near Idaho 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. 2.0 43 km NNE of Stanley, Idaho
  2. 1.8 33 km NNW of Challis, Idaho
  3. 1.7 32 km NNW of Challis, Idaho
  4. 1.8 43 km NNE of Stanley, Idaho
  5. 2.0 44 km NNE of Stanley, Idaho
  6. 2.1 43 km NNE of Stanley, Idaho
  7. 2.7 32 km NNW of Challis, Idaho
  8. 1.6 20 km NNW of Challis, Idaho
  9. 1.8 20 km NW of Challis, Idaho
  10. 1.5 8 km ESE of Challis, Idaho
  11. 1.6 southern Idaho
  12. 1.8 43 km NNE of Stanley, Idaho
  13. 2.6 34 km NNW of Challis, Idaho
  14. 1.5 36 km W of Challis, Idaho
  15. 1.9 20 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.