QuakeIndex

Earthquake · reviewed by a seismologist

M 3.4ml

21 km NW of Challis, Idaho

· 10 km deep · released about 1.9 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Custer County 44 kmLemhi County 51 kmValley County 99 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 3.4 (ml)
Depth
10 km below the surface
Felt
2 reports · strongest reported intensity II
Nearest
Custer County, 44 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1300 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 2 people have reported feeling it to USGS.

How big was it?

This earthquake released about 1.9 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.4 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 89,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 4,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 2,800× the energy of this one
  4. This earthquake M 3.4 about 1.9 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 4× 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 44.6528, -114.3980. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Custer County, ID 44 km (27 mi) NNW of here earthquakes near Custer County
Lemhi County, ID 51 km (31 mi) SW of here earthquakes near Lemhi County
Valley County, ID 99 km (61 mi) ESE of here earthquakes near Valley County
Boise County, ID 128 km (80 mi) NE of here earthquakes near Boise County
Beaverhead County, MT 130 km (81 mi) WSW of here earthquakes near Beaverhead County
Butte County, ID 145 km (90 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

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

  1. 2.2 21 km NNW of Challis, Idaho
  2. 1.6 23 km NNW of Challis, Idaho
  3. 1.6 30 km NNW of Challis, Idaho
  4. 2.6 southern Idaho
  5. 2.0 33 km NNW of Challis, Idaho
  6. 2.2 southern Idaho
  7. 2.1 28 km WNW of Challis, Idaho
  8. 2.3 32 km NNW of Challis, Idaho
  9. 2.3 32 km NNW of Challis, Idaho
  10. 2.5 33 km NNW of Challis, Idaho
  11. 2.5 33 km NNW of Challis, Idaho
  12. 2.0 southern Idaho
  13. 2.3 29 km WNW of Challis, Idaho
  14. 1.8 32 km NNW of Challis, Idaho
  15. 2.0 34 km NNW 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

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