QuakeIndex

Earthquake · reviewed by a seismologist

M 3.3ml

32 km NW of Kaycee, Wyoming

Yes. A magnitude 3.3 earthquake was recorded 32 km NW of Kaycee, Wyoming, at 9:49 am MDT on 3 September 2023 (15:49 UTC), 5.0 km deep. 1 person has reported feeling it to USGS.

· 5.0 km deep · released about 1.3 tons of TNT

10 km30 km60 km120 km N Johnson County 31 kmWashakie County 59 kmSheridan County 96 kmNatrona County 105 kmBig Horn County 108 kmCampbell County 117 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 3.3 (ml)
Depth
5.0 km below the surface
Felt
1 report · strongest reported intensity III
Nearest
Johnson County, 31 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1090 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 52 km (32 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 1.3 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.3 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 130,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 5,600× the energy of this one
  3. Magna, Utah 2020 M 5.7 4,000× the energy of this one
  4. This earthquake M 3.3 about 1.3 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 2.8× more

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 43.9179, -106.9300. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Johnson County, WY 31 km (19 mi) ENE earthquakes near Johnson County
Washakie County, WY 59 km (37 mi) W earthquakes near Washakie County
Sheridan County, WY 96 km (60 mi) N earthquakes near Sheridan County
Natrona County, WY 105 km (65 mi) S earthquakes near Natrona County
Big Horn County, WY 108 km (67 mi) NW earthquakes near Big Horn County
Campbell County, WY 117 km (73 mi) ENE earthquakes near Campbell 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 10 km SSE of Ten Sleep, 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.