QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6ml

Earthquake near West Yellowstone, MT

No earthquake was likely felt in West Yellowstone in the 24 hours to 2:48 pm MST (21:48 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 1.6 earthquake was recorded 50 km (31 mi) east of West Yellowstone, MT, at 9:21 am MST on 26 December 2019 (16:21 UTC), 4.0 km deep.

USGS: 39 km SSE of Mammoth, Wyoming

9:21 am MST, Dec 26, 2019 · · 4.0 km deep · released about 7.8 lb of TNT

10 km30 km60 km120 km N Teton County 68 kmPark County 72 kmPark County 90 kmFremont County 94 kmGallatin County 110 kmTeton County 116 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
9:21 am MST on 26 December 2019 ()
Where
50 km (31 mi) east of West Yellowstone, MT · earthquakes near West Yellowstone
Magnitude
M 1.6 (ml)
Depth
4.0 km below the surface
Felt
no reports yet
Nearest
Teton County, 68 km S
Nearest mapped fault
Eagle Bay fault, 16 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 2511 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 11 km (7 mi) from the epicentre. In West Yellowstone, 50 km away, the estimate is intensity I (not felt). 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 7.8 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,900,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,400,000× the energy of this one
  3. Around the size people start to feel M 3.0 120× the energy of this one
  4. This earthquake M 1.6 about 7.8 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists 12 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.5 14 km N of Madison Junction, Wyoming · 35 km WNW of this epicentre
  2. 6.3 22 km SW of Mammoth, Wyoming · 35 km WNW of this epicentre
  3. 6.0 21 km E of West Yellowstone, Montana · 29 km W of this epicentre
  4. 5.9 26 km SSE of Mammoth, Wyoming · 14 km NW of this epicentre
  5. 5.7 13 km SSW of Mammoth, Wyoming · 32 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 44.6588, -110.4743. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Teton County, WY 68 km (42 mi) S earthquakes near Teton County
Park County, WY 72 km (45 mi) ESE earthquakes near Park County
Park County, MT 90 km (56 mi) N earthquakes near Park County
Fremont County, ID 94 km (58 mi) WSW earthquakes near Fremont County
Gallatin County, MT 110 km (68 mi) NNW earthquakes near Gallatin County
Teton County, ID 116 km (72 mi) SSW earthquakes near Teton County

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

Aftershocks so far

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

  1. 2.0 15 km E of Hebgen Lake Estates, Montana
  2. 1.7 17 km E of Hebgen Lake Estates, Montana
  3. 1.5 32 km SE of West Yellowstone, Montana
  4. 1.5 10 km ENE of West Yellowstone, Montana
  5. 1.7 20 km S of Mammoth, Wyoming
  6. 1.6 39 km SSE of Mammoth, Wyoming
  7. 1.6 25 km S of Mammoth, Wyoming
  8. 1.8 37 km S of Silver Gate, Montana
  9. 1.5 56 km SE of West Yellowstone, Montana
  10. 1.5 12 km NE of West Yellowstone, Montana
  11. 1.6 34 km SW of Silver Gate, Montana
  12. 2.2 27 km SSW of Silver Gate, Montana
  13. 1.7 52 km S of Silver Gate, Montana
  14. 2.9 Wyoming
  15. 1.8 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.