QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9ml

Earthquake near Fort Washakie, WY

No earthquake was likely felt in Fort Washakie in the 24 hours to 7:43 am MST (14:43 UTC). The last one was M 3.8, 66 km (41 mi) SE, at 5:38 pm MST on 12 December 2025, estimated intensity II (weak) in town; 50 felt reports to USGS. Every earthquake near Fort Washakie

This page: a magnitude 2.9 earthquake was recorded 26 km (16 mi) southwest of Fort Washakie, WY, at 4:08 am MDT on 28 September 2025 (10:08 UTC), 5.6 km deep.

USGS: 25 km SW of Fort Washakie, Wyoming

4:08 am MDT, Sep 28, 2025 · · 5.6 km deep · released about 680 lb of TNT

10 km30 km60 km120 km N Fremont County 47 kmSublette County 67 kmHot Springs County 112 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
4:08 am MDT on 28 September 2025 ()
Where
26 km (16 mi) southwest of Fort Washakie, WY · earthquakes near Fort Washakie
Magnitude
M 2.9 (ml)
Depth
5.6 km below the surface
Felt
no reports yet
Nearest
Fremont County, 47 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 335 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 31 km (19 mi) from the epicentre. In Fort Washakie, 26 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.

Likely felt in: Lander 31 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 680 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 22,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 16,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.4× the energy of this one
  4. This earthquake M 2.9 about 680 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 5.0 10 km W of Atlantic City, Wyoming · 44 km SSE 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 42.8423, -109.1073. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Fremont County, WY 47 km (29 mi) ENE earthquakes near Fremont County
Sublette County, WY 67 km (41 mi) W earthquakes near Sublette County
Hot Springs County, WY 112 km (69 mi) NNE earthquakes near Hot Springs County
Washakie County, WY 164 km (102 mi) NE earthquakes near Washakie County

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

Aftershocks so far

1 earthquake has been recorded within 50 km since this one.

  1. 2.6 20 km ENE of Pinedale, 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.