QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5ml

47 km SE of Mammoth, Wyoming

Yes. A magnitude 1.5 earthquake was recorded 47 km SE of Mammoth, Wyoming, at 9:50 pm MDT on 9 September 2022 (03:50 UTC), 5.8 km deep.

· 5.8 km deep · released about 5.7 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Park County 61 kmTeton County 65 kmPark County 94 kmFremont County 102 kmGallatin County 118 kmTeton County 119 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 1.5 (ml)
Depth
5.8 km below the surface
Felt
no reports yet
Nearest
Park County, 61 km ESE
Nearest mapped fault
Eagle Bay fault, 12 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 1521 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 8 km (5 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 5.7 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,900,000× the energy of this one
  3. Around the size people start to feel M 3.0 170× the energy of this one
  4. This earthquake M 1.5 about 5.7 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 11,000 times the energy of this one.

Before 2016, the USGS record lists 11 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.5 14 km N of Madison Junction, Wyoming · 46 km WNW of this epicentre
  2. 6.3 22 km SW of Mammoth, Wyoming · 46 km WNW of this epicentre
  3. 6.0 21 km E of West Yellowstone, Montana · 39 km W of this epicentre
  4. 5.9 26 km SSE of Mammoth, Wyoming · 24 km WNW of this epicentre
  5. 5.7 13 km SSW of Mammoth, Wyoming · 42 km NW 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 44.6287, -110.3425. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Park County, WY 61 km (38 mi) ESE earthquakes near Park County
Teton County, WY 65 km (40 mi) S earthquakes near Teton County
Park County, MT 94 km (58 mi) N earthquakes near Park County
Fremont County, ID 102 km (63 mi) WSW earthquakes near Fremont County
Gallatin County, MT 118 km (73 mi) NNW earthquakes near Gallatin County
Teton County, ID 119 km (74 mi) SW earthquakes near Teton County

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

Aftershocks so far

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

  1. 1.6 35 km S of Silver Gate, Montana
  2. 1.5 23 km SSW of Mammoth, Wyoming
  3. 2.0 22 km SSW of Mammoth, Wyoming
  4. 2.0 68 km ESE of West Yellowstone, Montana
  5. 2.6 23 km SSW of Mammoth, Wyoming
  6. 2.1 23 km SSW of Mammoth, Wyoming
  7. 2.1 23 km SSW of Mammoth, Wyoming
  8. 1.5 23 km SSW of Mammoth, Wyoming
  9. 1.9 23 km SSW of Mammoth, Wyoming
  10. 1.9 23 km SSW of Mammoth, Wyoming
  11. 2.7 22 km SSW of Mammoth, Wyoming
  12. 2.1 Wyoming
  13. 2.0 23 km SSW of Mammoth, Wyoming
  14. 1.7 23 km SSW of Mammoth, Wyoming
  15. 2.5 23 km SSW of Mammoth, 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.