QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

19 km NNW of Clayton, Idaho

· 7.0 km deep · released about 15 lb of TNT

10 km30 km60 km120 km N Custer County 25 kmLemhi County 73 kmValley County 102 kmCamas County 105 kmBoise County 110 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 1.8 (ml)
Depth
7.0 km below the surface
Felt
no reports yet
Nearest
Custer County, 25 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 857 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 15 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 710,000× the energy of this one
  3. Around the size people start to feel M 3.0 63× the energy of this one
  4. This earthquake M 1.8 about 15 lb of TNT

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 44.4267, -114.4812. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Custer County, ID 25 km (15 mi) NW of here earthquakes near Custer County
Lemhi County, ID 73 km (45 mi) SW of here earthquakes near Lemhi County
Valley County, ID 102 km (63 mi) ESE of here earthquakes near Valley County
Camas County, ID 105 km (65 mi) NNE of here earthquakes near Camas County
Boise County, ID 110 km (68 mi) ENE of here earthquakes near Boise County
Blaine County, ID 122 km (76 mi) NNW of here earthquakes near Blaine County

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

Aftershocks so far

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

  1. 1.9 5 km NW of Stanley, Idaho
  2. 1.8 4 km NNW of Stanley, Idaho
  3. 1.7 5 km NNW of Stanley, Idaho
  4. 1.8 6 km NW of Stanley, Idaho
  5. 1.9 20 km NNW of Challis, Idaho
  6. 1.8 20 km NNW of Challis, Idaho
  7. 1.6 16 km NE of Stanley, Idaho
  8. 2.4 15 km NNE of Stanley, Idaho
  9. 1.6 9 km NE of Stanley, Idaho
  10. 1.8 16 km NE of Stanley, Idaho
  11. 1.7 16 km NE of Stanley, Idaho
  12. 2.0 16 km NE of Stanley, Idaho
  13. 1.5 20 km SSW of Clayton, Idaho
  14. 1.7 4 km N of Stanley, Idaho
  15. 1.7 20 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.2 on 2020-06-09 — it released about 4,000 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.