QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1ml

Earthquake near West Yellowstone, MT

No earthquake was likely felt in West Yellowstone in the 24 hours to 8:31 am MST (15:31 UTC). The last one was M 2.8, 11 km (7 mi) NNW, at 1:21 am MDT on 8 September 2026, estimated intensity II (weak) in town. Every earthquake near West Yellowstone

This page: a magnitude 2.1 earthquake was recorded 27 km (17 mi) east-southeast of West Yellowstone, MT, at 11:12 am MDT on 21 June 2021 (17:12 UTC), 6.1 km deep.

USGS: 27 km ESE of West Yellowstone, Montana

11:12 am MDT, Jun 21, 2021 · · 6.1 km deep · released about 40 lb of TNT

Every earthquake near West Yellowstone Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Teton County 68 kmFremont County 71 kmPark County 94 kmPark County 97 kmTeton County 100 kmGallatin County 106 kmMadison County 115 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
11:12 am MDT on 21 June 2021 ()
Where
27 km (17 mi) east-southeast of West Yellowstone, MT · earthquakes near West Yellowstone
Montana today
every earthquake in Montana in the last 24 hours
Magnitude
M 2.1 (ml)
Depth
6.1 km below the surface
Felt
no reports yet
Nearest
Teton County, 68 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1969 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 16 km (10 mi) from the epicentre. In West Yellowstone, 27 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 40 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 380,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 270,000× the energy of this one
  3. Around the size people start to feel M 3.0 24× the energy of this one
  4. This earthquake M 2.1 about 40 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 4.4 on 2017-06-16 — about 2,600 times the energy of this one.

Before 2016, the USGS record lists 13 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.2 The 1959 Hebgen Lake, Montana Earthquake · 40 km WNW of this epicentre
  2. 6.5 14 km N of Madison Junction, Wyoming · 20 km NNW of this epicentre
  3. 6.3 22 km SW of Mammoth, Wyoming · 24 km NNW of this epicentre
  4. 6.0 21 km E of West Yellowstone, Montana · 7 km NW of this epicentre
  5. 5.9 26 km SSE of Mammoth, Wyoming · 20 km NE 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 44.6058, -110.7667. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Teton County, WY 68 km (42 mi) SSE earthquakes near Teton County
Fremont County, ID 71 km (44 mi) SW earthquakes near Fremont County
Park County, WY 94 km (58 mi) E earthquakes near Park County
Park County, MT 97 km (60 mi) N earthquakes near Park County
Teton County, ID 100 km (62 mi) SSW earthquakes near Teton County
Gallatin County, MT 106 km (66 mi) NNW earthquakes near Gallatin 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. 1.7 64 km SSE of Mammoth, Wyoming
  2. 1.8 63 km ESE of West Yellowstone, Montana
  3. 1.8 63 km ESE of West Yellowstone, Montana
  4. 1.8 64 km ESE of West Yellowstone, Montana
  5. 1.8 64 km ESE of West Yellowstone, Montana
  6. 1.7 64 km ESE of West Yellowstone, Montana
  7. 1.6 64 km ESE of West Yellowstone, Montana
  8. 1.5 64 km ESE of West Yellowstone, Montana
  9. 1.8 64 km ESE of West Yellowstone, Montana
  10. 2.0 64 km ESE of West Yellowstone, Montana
  11. 2.0 63 km ESE of West Yellowstone, Montana
  12. 1.6 28 km E of West Yellowstone, Montana
  13. 1.6 2 km SSE of Hebgen Lake Estates, Montana
  14. 2.7 28 km E of West Yellowstone, Montana
  15. 1.9 45 km ENE of Warm River, Idaho

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.