Earthquake · reviewed by a seismologist
M 1.8ml
23 km ENE of Wilsall, Montana
- When
- Magnitude
- M 1.8 (ml)
- Depth
- 9.6 km below the surface
- Felt
- no reports yet
- Nearest
- Sweet Grass County, 45 km SE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 364 days ago
This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.
How big was it?
This earthquake released about 13 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 5.7 810,000× the energy of this one
- Around the size people start to feel M 3.0 72× the energy of this one
- This earthquake M 1.8 about 13 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.
Where
Epicentre 46.0773, -110.3863. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction | |
|---|---|---|---|
| Sweet Grass County, MT | 45 km (28 mi) | NW of here | earthquakes near Sweet Grass County |
| Wheatland County, MT | 62 km (38 mi) | SW of here | earthquakes near Wheatland County |
| Park County, MT | 69 km (43 mi) | N of here | earthquakes near Park County |
| Meagher County, MT | 70 km (43 mi) | SE of here | earthquakes near Meagher County |
| Gallatin County, MT | 87 km (54 mi) | NE of here | earthquakes near Gallatin County |
| Broadwater County, MT | 90 km (56 mi) | ESE of here | earthquakes near Broadwater County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
No further earthquakes have been recorded within 50 km since this one.
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.