QuakeIndex

Earthquake · reviewed by a seismologist

M 2.6ml

Earthquake near Afton, WY

No earthquake was likely felt in Afton in the 24 hours to 11:18 pm MST (06:18 UTC). The last one was M 2.3, 14 km (9 mi) W, at 3:44 pm MDT on 19 May 2026, estimated intensity II (weak) in town. Every earthquake near Afton

This page: a magnitude 2.6 earthquake was recorded 7 km (4 mi) west-northwest of Afton, WY, at 6:04 am MDT on 22 August 2019 (12:04 UTC), 10 km deep. 6 people have reported feeling it to USGS.

USGS: 5 km S of Auburn, Wyoming

6:04 am MDT, Aug 22, 2019 · · 10 km deep · released about 240 lb of TNT

10 km30 km60 km120 km N Caribou County 44 kmBear Lake County 57 kmLincoln County 63 kmBonneville County 88 kmSublette County 89 kmFranklin County 92 kmBannock County 100 kmTeton County 115 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
6:04 am MDT on 22 August 2019 ()
Where
7 km (4 mi) west-northwest of Afton, WY · earthquakes near Afton
Magnitude
M 2.6 (ml)
Depth
10 km below the surface
Felt
6 reports · strongest reported intensity III
Nearest
Caribou County, 44 km W
Nearest mapped fault
Grand Valley fault, 8 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 2561 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 21 km (13 mi) from the epicentre. In Afton, 7 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.

Earthquakes near other towns within 30 km: Star Valley Ranch.

How big was it?

This earthquake released about 240 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 63,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 45,000× the energy of this one
  3. Around the size people start to feel M 3.0 4× the energy of this one
  4. This earthquake M 2.6 about 240 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 5.3 on 2017-09-02 — about 11,000 times the energy of this one.

Before 2016, the USGS record lists 3 earthquakes of M5 or more within 50 km:

  1. 5.8 4 km SSE of Auburn, Wyoming · 4 km NE of this epicentre
  2. 5.3 Southeastern Idaho · 37 km NW of this epicentre
  3. 5.3 29 km WSW of Freedom, Idaho · 38 km WNW 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 42.7398, -111.0099. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Caribou County, ID 44 km (27 mi) W earthquakes near Caribou County
Bear Lake County, ID 57 km (35 mi) SSW earthquakes near Bear Lake County
Lincoln County, WY 63 km (39 mi) SSE earthquakes near Lincoln County
Bonneville County, ID 88 km (55 mi) NW earthquakes near Bonneville County
Sublette County, WY 89 km (56 mi) E earthquakes near Sublette County
Franklin County, ID 92 km (57 mi) SW earthquakes near Franklin County

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

Aftershocks so far

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

  1. 2.0 19 km SW of Fairview, Wyoming
  2. 1.8 7 km E of Soda Springs, Idaho
  3. 3.1 21 km WNW of Auburn, Wyoming
  4. 1.7 11 km E of Soda Springs, Idaho
  5. 1.8 13 km ESE of Soda Springs, Idaho
  6. 1.9 10 km ESE of Soda Springs, Idaho
  7. 2.6 16 km ENE of Soda Springs, Idaho
  8. 1.5 10 km ENE of Soda Springs, Idaho
  9. 1.6 12 km ESE of Soda Springs, Idaho
  10. 1.9 10 km E of Soda Springs, Idaho
  11. 1.6 6 km ENE of Soda Springs, Idaho
  12. 2.9 9 km ESE of Soda Springs, Idaho
  13. 2.0 11 km ESE of Soda Springs, Idaho
  14. 2.3 19 km WSW of Fairview, Wyoming
  15. 2.4 8 km WSW of Smoot, Wyoming

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.