Earthquake · reviewed by a seismologist
M 1.7md
56 km SSW of Silver Gate, Montana
Yes. A magnitude 1.7 earthquake was recorded 56 km SSW of Silver Gate, Montana, at 7:16 pm MDT on 2 August 2018 (01:16 UTC), 6.1 km deep.
- When
- Montana today
- every earthquake in Montana in the last 24 hours
- Magnitude
- M 1.7 (md)
- Depth
- 6.1 km below the surface
- Felt
- no reports yet
- Nearest
- Park County, 45 km E
- Nearest mapped fault
- Buffalo Fork fault, 17 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 3023 days ago
Earthquake alerts for West Yellowstone, MT
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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 11 km (7 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 12 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 1,200,000× the energy of this one
- Magna, Utah 2020 M 5.7 870,000× the energy of this one
- Around the size people start to feel M 3.0 78× the energy of this one
- This earthquake M 1.7 about 12 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 3 earthquakes of M5 or more within 50 km:
- 5.9 26 km SSE of Mammoth, Wyoming · 44 km NW of this epicentre
- 5.1 51 km ESE of West Yellowstone, Montana · 26 km W of this epicentre
- 5.0 62 km ESE of West Yellowstone, Montana · 21 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 44.5123, -110.1587. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Park County, WY | 45 km (28 mi) | E | earthquakes near Park County |
| Teton County, WY | 56 km (35 mi) | SSW | earthquakes near Teton County |
| Park County, MT | 110 km (68 mi) | NNW | earthquakes near Park County |
| Fremont County, ID | 110 km (69 mi) | WSW | earthquakes near Fremont County |
| Teton County, ID | 118 km (74 mi) | SW | earthquakes near Teton County |
| Carbon County, MT | 119 km (74 mi) | NE | earthquakes near Carbon 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.
- 2.4 49 km SE of West Yellowstone, Montana
- 1.6 39 km SSE of Mammoth, Wyoming
- 2.0 39 km SSE of Mammoth, Wyoming
- 1.9 39 km SSE of Mammoth, Wyoming
- 2.4 51 km SSW of Silver Gate, Montana
- 1.7 39 km SSE of Mammoth, Wyoming
- 2.8 30 km SW of Silver Gate, Montana
- 2.6 34 km SW of Silver Gate, Montana
- 2.6 36 km SW of Silver Gate, Montana
- 2.8 34 km SW of Silver Gate, Montana
- 2.3 34 km SW of Silver Gate, Montana
- 2.0 33 km SW of Silver Gate, Montana
- 2.4 34 km SW of Silver Gate, Montana
- 1.9 38 km SSE of Mammoth, Wyoming
- 1.6 48 km SSE of Mammoth, 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
- 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.