QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1ml

Earthquake near West Yellowstone, MT

No earthquake was likely felt in West Yellowstone in the 24 hours to 6:44 am MST (13:44 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 3.1 earthquake was recorded 18 km (11 mi) northeast of West Yellowstone, MT, at 8:02 am MDT on 28 June 2021 (14:02 UTC), 11 km deep. 1 person has reported feeling it to USGS.

USGS: 17 km NE of West Yellowstone, Montana

8:02 am MDT, Jun 28, 2021 · · 11 km deep · released about 1,500 lb of TNT

10 km30 km60 km120 km N Fremont County 74 kmPark County 85 kmTeton County 87 kmGallatin County 87 kmMadison County 101 kmPark County 109 kmTeton County 113 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
8:02 am MDT on 28 June 2021 ()
Where
18 km (11 mi) northeast of West Yellowstone, MT · earthquakes near West Yellowstone
Montana today
every earthquake in Montana in the last 24 hours
Magnitude
M 3.1 (ml)
Depth
11 km below the surface
Felt
1 report · strongest reported intensity I
Nearest
Fremont County, 74 km SW
Nearest mapped fault
Red Canyon fault, 7 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 1889 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 42 km (26 mi) from the epicentre. In West Yellowstone, 18 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.

Likely felt in: West Yellowstone 18 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1,500 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 220,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 9,800× the energy of this one
  3. Magna, Utah 2020 M 5.7 6,900× the energy of this one
  4. This earthquake M 3.1 about 1,500 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.6× 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

The largest earthquake within 50 km since 2016 was M 4.4 on 2017-06-16 — about 68 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 · 23 km WNW of this epicentre
  2. 6.5 14 km N of Madison Junction, Wyoming · 3 km NE of this epicentre
  3. 6.3 22 km SW of Mammoth, Wyoming · 8 km NNE of this epicentre
  4. 6.0 21 km E of West Yellowstone, Montana · 13 km SSE of this epicentre
  5. 5.9 26 km SSE of Mammoth, Wyoming · 25 km E 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 44.7518, -110.9168. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Fremont County, ID 74 km (46 mi) SW earthquakes near Fremont County
Park County, MT 85 km (53 mi) NNE earthquakes near Park County
Teton County, WY 87 km (54 mi) SSE earthquakes near Teton County
Gallatin County, MT 87 km (54 mi) NNW earthquakes near Gallatin County
Madison County, MT 101 km (63 mi) NW earthquakes near Madison County
Park County, WY 109 km (67 mi) ESE earthquakes near Park County

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

Aftershocks so far

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

  1. 1.6 28 km E of West Yellowstone, Montana
  2. 1.6 2 km SSE of Hebgen Lake Estates, Montana
  3. 2.7 28 km E of West Yellowstone, Montana
  4. 1.7 45 km SSE of Mammoth, Wyoming
  5. 1.6 27 km S of Mammoth, Wyoming
  6. 2.6 28 km E of West Yellowstone, Montana
  7. 1.8 27 km S of Mammoth, Wyoming
  8. 1.5 18 km NE of West Yellowstone, Montana
  9. 1.9 5 km ESE of Hebgen Lake Estates, Montana
  10. 2.2 17 km ENE of West Yellowstone, Montana
  11. 1.6 9 km E of Hebgen Lake Estates, Montana
  12. 1.6 17 km NE of West Yellowstone, Montana
  13. 1.7 18 km ENE of West Yellowstone, Montana
  14. 2.2 17 km ENE of West Yellowstone, Montana
  15. 1.5 18 km NE of West Yellowstone, 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.