QuakeIndex

Earthquake · reviewed by a seismologist

M 3.2ml

Earthquake near Challis, ID

No earthquake was likely felt in Challis in the 24 hours to 9:46 pm MST (04:46 UTC). The last one was M 2.0, 9 km (6 mi) SSW, at 1:32 am MDT on 17 August 2026, estimated intensity II (weak) in town. Every earthquake near Challis

This page: a magnitude 3.2 earthquake was recorded 22 km (14 mi) northwest of Challis, ID, at 1:54 pm MDT on 6 September 2023 (19:54 UTC), 17 km deep. 2 people have reported feeling it to USGS.

USGS: 22 km NW of Challis, Idaho

1:54 pm MDT, Sep 6, 2023 · · 17 km deep · released about 1,900 lb of TNT

Every earthquake near Challis Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Custer County 45 kmLemhi County 51 kmValley County 98 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
1:54 pm MDT on 6 September 2023 ()
Where
22 km (14 mi) northwest of Challis, ID · earthquakes near Challis
Idaho today
every earthquake in Idaho in the last 24 hours
Magnitude
M 3.2 (ml)
Depth
17 km below the surface
Felt
2 reports · strongest reported intensity III
Nearest
Custer County, 45 km SSE
Nearest mapped fault
Lost River fault, 19 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1090 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 43 km (27 mi) from the epicentre. In Challis, 22 km away, the estimate is intensity II (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

Likely felt in: Challis 22 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1,900 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 180,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 7,900× the energy of this one
  3. Magna, Utah 2020 M 5.7 5,600× the energy of this one
  4. This earthquake M 3.2 about 1,900 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 2× 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.

For this area

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:

  1. 6.1 37 km N of Stanley, Idaho · 40 km WSW of this epicentre
  2. 5.6 18 km ESE of Challis, Idaho · 38 km SE of this epicentre
  3. 5.5 22 km E of Clayton, Idaho · 48 km SSE of this epicentre
  4. 5.1 9 km SE of Challis, Idaho · 32 km SE of this epicentre
  5. 5.0 9 km E of Challis, Idaho · 29 km SE of this epicentre

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 44.6605, -114.4085. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Custer County, ID 45 km (28 mi) SSE earthquakes near Custer County
Lemhi County, ID 51 km (32 mi) NE earthquakes near Lemhi County
Valley County, ID 98 km (61 mi) WNW earthquakes near Valley County
Boise County, ID 128 km (80 mi) SW earthquakes near Boise County
Butte County, ID 146 km (91 mi) SE 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. 2.4 45 km NNE of Stanley, Idaho
  2. 1.7 24 km SE of Challis, Idaho
  3. 1.9 43 km NNE of Stanley, Idaho
  4. 2.1 43 km NNE of Stanley, Idaho
  5. 2.0 43 km NNE of Stanley, Idaho
  6. 1.8 33 km NNW of Challis, Idaho
  7. 1.7 32 km NNW of Challis, Idaho
  8. 1.8 43 km NNE of Stanley, Idaho
  9. 2.0 44 km NNE of Stanley, Idaho
  10. 2.1 43 km NNE of Stanley, Idaho
  11. 2.7 32 km NNW of Challis, Idaho
  12. 1.6 20 km NNW of Challis, Idaho
  13. 1.8 20 km NW of Challis, Idaho
  14. 1.5 8 km ESE of Challis, Idaho
  15. 1.6 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.