M1.6 earthquake Western Montana
A magnitude 1.6 earthquake struck in Western Montana on Mon, Aug 21, 2017, 2:49 AM MDT (08:49 UTC), 6 km (4 mi) below the surface.
A larger quake followed: M2.1 43 km W of Hebgen Lake Estates, Montana. This one was a foreshock.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 1.6 (ML, local (Richter)), micro
- Magnitude from
- Montana Bureau of Mines and Geology
- Local time
- UTC
- 2017-08-21 08:49:18 UTC
- Depth
- 6.2 km (3.8 mi), shallow
- Epicenter
- 45.376° N, 112.612° W
- Region
- Montana
- Tsunami flag
- No
- Status
- Reviewed by a seismologist
Did you feel it?
No one has reported feeling this quake to the USGS.
How well it is located
Reviewed by a seismologist.
- Location uncertainty
- About 0.3 km horizontally, 0.3 km in depth
- Magnitude uncertainty
- ±0.27
- Depth from
- From location
- Station coverage gap
- 88°
- Stations used
- 15
Nearest places
Distance and direction from each place to the epicenter, with its forecast.
Nearby
Within 100 km, magnitude 1.5 and up: 3 in the 60 days after this one and 2 in the 30 days before it.
After
- 2.143 km W of Hebgen Lake Estates, Montana · 3315 days ago · 10 km deep · 98 km away
- 1.728 km SSE of Virginia City, Montana · 3283 days ago · 10 km deep · 70 km away
- 2.029 km NNE of Spencer, Idaho · 3279 days ago · 7 km deep · 93 km away
Before
Earthquakes todayMontana earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event mb80246869. Read Sun, Oct 4, 2026, 12:22 AM UTC.