QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5ml

25 km S of Stanley, Idaho

Yes. A magnitude 2.5 earthquake was recorded 25 km S of Stanley, Idaho, at 3:06 pm MST on 17 December 2020 (22:06 UTC), 10 km deep.

· 10 km deep · released about 170 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Camas County 56 kmBoise County 61 kmCuster County 64 kmElmore County 78 kmBlaine County 104 kmValley County 110 kmGooding County 114 kmGem County 115 kmAda County 120 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
Idaho today
every earthquake in Idaho in the last 24 hours
Magnitude
M 2.5 (ml)
Depth
10 km below the surface
Felt
no reports yet
Nearest
Camas County, 56 km SSE
Nearest mapped fault
Sawtooth fault, 5 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 2083 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 20 km (12 mi) from the epicentre. 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.

How big was it?

This earthquake released about 170 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 89,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 63,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.6× the energy of this one
  4. This earthquake M 2.5 about 170 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.

For this area

The largest earthquake within 50 km since 2016 was M 4.8 on 2020-04-01 — about 2,800 times the energy of this one.

Before 2016, the USGS record since 1900 lists no earthquake of M5 or more within 50 km.

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 43.9908, -114.9578. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Camas County, ID 56 km (35 mi) SSE earthquakes near Camas County
Boise County, ID 61 km (38 mi) W earthquakes near Boise County
Custer County, ID 64 km (40 mi) ENE earthquakes near Custer County
Elmore County, ID 78 km (49 mi) SSW earthquakes near Elmore County
Blaine County, ID 104 km (65 mi) SE earthquakes near Blaine County
Valley County, ID 110 km (68 mi) NNW earthquakes near Valley County

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

Aftershocks so far

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

  1. 2.1 10 km NE of Stanley, Idaho
  2. 2.2 20 km WNW of Stanley, Idaho
  3. 1.7 21 km WNW of Stanley, Idaho
  4. 1.9 6 km W of Stanley, Idaho
  5. 2.3 6 km W of Stanley, Idaho
  6. 2.3 6 km W of Stanley, Idaho
  7. 1.9 5 km N of Stanley, Idaho
  8. 1.7 15 km SW of Stanley, Idaho
  9. 2.4 23 km WNW of Stanley, Idaho
  10. 1.9 21 km WNW of Stanley, Idaho
  11. 2.4 23 km WNW of Stanley, Idaho
  12. 2.8 11 km WNW of Stanley, Idaho
  13. 1.8 20 km WNW of Stanley, Idaho
  14. 1.8 southern Idaho
  15. 1.9 24 km NW 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.

On USGS

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