QuakeIndex

Earthquake · reviewed by a seismologist

M 3.8mwr

18 km NE of Stanley, Idaho

· 15 km deep · released about 7.6 tons of TNT

10 km30 km60 km120 km N Custer County 44 kmBoise County 84 kmValley County 86 kmCamas County 95 kmLemhi County 96 kmElmore 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 3.8 (mwr)
Depth
15 km below the surface
Felt
14 reports · strongest reported intensity IV
Measured shaking
intensity III (ShakeMap)
Nearest
Custer County, 44 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1759 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 14 people have reported feeling it to USGS.

How big was it?

This earthquake released about 7.6 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.8 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 22,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 1,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 710× the energy of this one
  4. This earthquake M 3.8 about 7.6 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 16× 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 44.3531, -114.7974. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Custer County, ID 44 km (28 mi) WNW of here earthquakes near Custer County
Boise County, ID 84 km (52 mi) ENE of here earthquakes near Boise County
Valley County, ID 86 km (53 mi) SE of here earthquakes near Valley County
Camas County, ID 95 km (59 mi) N of here earthquakes near Camas County
Lemhi County, ID 96 km (60 mi) SW of here earthquakes near Lemhi County
Elmore County, ID 119 km (74 mi) NNE of here earthquakes near Elmore County

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

Aftershocks so far

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

  1. 2.2 33 km NW of Stanley, Idaho
  2. 2.3 11 km NW of Stanley, Idaho
  3. 2.3 7 km NW of Stanley, Idaho
  4. 3.0 11 km NW of Stanley, Idaho
  5. 2.5 8 km NW of Stanley, Idaho
  6. 2.6 14 km NW of Stanley, Idaho
  7. 2.4 42 km NNW of Stanley, Idaho
  8. 2.2 18 km NNE of Stanley, Idaho
  9. 2.0 17 km NNE of Stanley, Idaho
  10. 2.1 6 km NW of Stanley, Idaho
  11. 1.7 7 km NW of Stanley, Idaho
  12. 2.3 6 km NW of Stanley, Idaho
  13. 1.7 19 km NE of Stanley, Idaho
  14. 2.1 9 km NNE of Stanley, Idaho
  15. 2.8 11 km NNW of Stanley, 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.

For this area

The largest earthquake within 50 km in our catalogue was M 6.5 on 2020-03-31 — it released about 11,000 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.