QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5ml

Earthquake near Bar Nunn, WY

No earthquake was likely felt in Bar Nunn in the 24 hours to 9:49 am MST (16:49 UTC). The last one was M 3.6, 260 km (162 mi) ENE, at 8:14 pm MST on 8 March 2025, estimated intensity II (weak) in town; 7 felt reports to USGS. Every earthquake near Bar Nunn

This page: a magnitude 2.5 earthquake was recorded 49 km (31 mi) north of Bar Nunn, WY, at 6:35 am MST on 1 January 2021 (13:35 UTC), 14 km deep.

USGS: 7 km SSE of Edgerton, Wyoming

57 km (35 mi) N of Casper, WY

6:35 am MST, Jan 1, 2021 · · 14 km deep · released about 170 lb of TNT

10 km30 km60 km120 km N Natrona County 60 kmConverse County 70 kmJohnson County 83 kmCampbell 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
6:35 am MST on 1 January 2021 ()
Where
49 km (31 mi) north of Bar Nunn, WY · earthquakes near Bar Nunn
Magnitude
M 2.5 (ml)
Depth
14 km below the surface
Felt
no reports yet
Nearest
Natrona County, 60 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2069 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 17 km (11 mi) from the epicentre. In Bar Nunn, 49 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.

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

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

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 43.3502, -106.2250. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Natrona County, WY 60 km (38 mi) SW earthquakes near Natrona County
Converse County, WY 70 km (43 mi) SE earthquakes near Converse County
Johnson County, WY 83 km (51 mi) NNW earthquakes near Johnson County
Campbell County, WY 110 km (68 mi) NNE earthquakes near Campbell County
Washakie County, WY 130 km (81 mi) WNW earthquakes near Washakie County

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

Aftershocks so far

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

  1. 3.0 12 km SSE of Edgerton, Wyoming
  2. 3.8 12 km NW of Rolling Hills, 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.