Earthquake · reviewed by a seismologist
M 1.8md
37 km SSE of Silver Gate, Montana
Yes. A magnitude 1.8 earthquake was recorded 37 km SSE of Silver Gate, Montana, at 11:10 am MDT on 27 April 2025 (17:10 UTC), 8.7 km deep.
- When
- Montana today
- every earthquake in Montana in the last 24 hours
- Magnitude
- M 1.8 (md)
- Depth
- 8.7 km below the surface
- Felt
- no reports yet
- Nearest
- Park County, 30 km SE
- Nearest mapped fault
- Mirror Plateau faults, 22 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 562 days ago
Earthquake alerts for Cody, WY
Get a notification in this browser when USGS records an earthquake near Cody, WY. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
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 10 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 14 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.
- Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
- Magna, Utah 2020 M 5.7 790,000× the energy of this one
- Around the size people start to feel M 3.0 70× the energy of this one
- This earthquake M 1.8 about 14 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 4,700 times the energy of this one.
Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:
- 5.0 62 km ESE of West Yellowstone, Montana · 49 km WSW 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 44.6767, -109.8737. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Park County, WY | 30 km (19 mi) | SE | earthquakes near Park County |
| Teton County, WY | 82 km (51 mi) | SSW | earthquakes near Teton County |
| Carbon County, MT | 90 km (56 mi) | NE | earthquakes near Carbon County |
| Park County, MT | 102 km (63 mi) | NNW | earthquakes near Park County |
| Stillwater County, MT | 116 km (72 mi) | NNE | earthquakes near Stillwater County |
| Gallatin County, MT | 138 km (86 mi) | NW | earthquakes near Gallatin County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
50 earthquakes have been recorded within 50 km since this one.
- 0.6 66 km ESE of West Yellowstone, Montana
- 1.8 36 km S of Silver Gate, Montana
- 0.4 49 km SSE of Mammoth, Wyoming
- 0.6 48 km SSE of Mammoth, Wyoming
- 0.9 34 km S of Silver Gate, Montana
- 1.5 35 km S of Silver Gate, Montana
- 0.7 51 km SE of Mammoth, Wyoming
- 1.9 35 km S of Silver Gate, Montana
- 0.7 45 km SE of Mammoth, Wyoming
- 1.2 29 km SSW of Silver Gate, Montana
- 1.1 29 km SSW of Silver Gate, Montana
- 1.8 40 km SSW of Silver Gate, Montana
- 1.2 47 km SE of Mammoth, Wyoming
- 0.8 34 km SW of Silver Gate, Montana
- 1.5 37 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
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.