QuakeIndex

Earthquake · reviewed by a seismologist

M 4.2mwr

10 km NW of Stanley, Idaho

· 7.6 km deep · released about 30 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Boise County 62 kmCuster County 63 kmValley County 79 kmCamas County 89 kmElmore County 104 kmGem County 110 kmLemhi County 117 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 4.2 (mwr)
Depth
7.6 km below the surface
Felt
141 reports · strongest reported intensity IV
Measured shaking
intensity IV (ShakeMap)
USGS impact alert
green
Nearest
Boise County, 62 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2227 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon. 141 people have reported feeling it to USGS.

How big was it?

This earthquake released about 30 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 5,600× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 250× the energy of this one
  3. Magna, Utah 2020 M 5.7 180× the energy of this one
  4. This earthquake M 4.2 about 30 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 63× 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 44.2753, -115.0480. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Boise County, ID 62 km (39 mi) ENE of here earthquakes near Boise County
Custer County, ID 63 km (39 mi) W of here earthquakes near Custer County
Valley County, ID 79 km (49 mi) SE of here earthquakes near Valley County
Camas County, ID 89 km (55 mi) NNW of here earthquakes near Camas County
Elmore County, ID 104 km (64 mi) NNE of here earthquakes near Elmore County
Gem County, ID 110 km (69 mi) ENE of here earthquakes near Gem 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. 2.3 12 km W of Stanley, Idaho
  2. 1.8 22 km WNW of Stanley, Idaho
  3. 1.7 42 km NNW of Stanley, Idaho
  4. 2.5 26 km NW of Stanley, Idaho
  5. 1.8 27 km NW of Stanley, Idaho
  6. 3.1 25 km NW of Stanley, Idaho
  7. 2.2 25 km NW of Stanley, Idaho
  8. 2.1 27 km NW of Stanley, Idaho
  9. 2.3 27 km NW of Stanley, Idaho
  10. 2.2 29 km NW of Stanley, Idaho
  11. 2.4 26 km NW of Stanley, Idaho
  12. 2.1 24 km WNW of Stanley, Idaho
  13. 2.2 27 km NW of Stanley, Idaho
  14. 2.9 26 km NW of Stanley, Idaho
  15. 2.2 12 km W 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 2,800 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.