QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

69 km WSW of Cody, Wyoming

Yes. A magnitude 1.8 earthquake was recorded 69 km WSW of Cody, Wyoming, at 11:27 am MST on 25 November 2023 (18:27 UTC), 10 km deep.

· 10 km deep · released about 15 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Park County 28 kmTeton County 54 kmCarbon County 118 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 1.8 (md)
Depth
10 km below the surface
Felt
no reports yet
Nearest
Park County, 28 km ENE
Nearest mapped fault
Upper Yellowstone Valley faults, 21 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 1081 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 9 km (6 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 15 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 710,000× the energy of this one
  3. Around the size people start to feel M 3.0 63× the energy of this one
  4. This earthquake M 1.8 about 15 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 4.2 on 2022-05-11 — about 4,300 times the energy of this one.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 5.1 51 km ESE of West Yellowstone, Montana · 50 km WNW of this epicentre
  2. 5.0 62 km ESE of West Yellowstone, Montana · 40 km W 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 44.3627, -109.9017. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Park County, WY 28 km (18 mi) ENE earthquakes near Park County
Teton County, WY 54 km (34 mi) SW earthquakes near Teton County
Carbon County, MT 118 km (73 mi) NE earthquakes near Carbon County
Teton County, ID 124 km (77 mi) WSW earthquakes near Teton County
Hot Springs County, WY 137 km (85 mi) ESE earthquakes near Hot Springs County

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

Aftershocks so far

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

  1. 2.4 37 km S of Silver Gate, Montana
  2. 1.7 46 km SSE of Mammoth, Wyoming
  3. 1.7 46 km SSE of Mammoth, Wyoming
  4. 1.6 47 km SSE of Mammoth, Wyoming
  5. 1.7 44 km SE of Mammoth, Wyoming
  6. 1.6 65 km NNE of Kelly, Wyoming
  7. 1.8 64 km NNE of Kelly, Wyoming
  8. 1.6 48 km SSW of Silver Gate, Montana
  9. 1.8 48 km SSW of Silver Gate, Montana
  10. 2.5 48 km SSW of Silver Gate, Montana
  11. 2.3 64 km NNE of Kelly, Wyoming
  12. 2.1 61 km NNE of Kelly, Wyoming
  13. 2.1 38 km S of Silver Gate, Montana
  14. 1.9 48 km SSE of Mammoth, Wyoming
  15. 2.0 34 km S of Silver Gate, Montana

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.