Earthquake · reviewed by a seismologist
M 1.6ml
Earthquake near Hamilton, MT
No earthquake was likely felt in Hamilton in the 24 hours to 5:55 pm MST (00:55 UTC). The last one was M 1.6, 7 km (4 mi) SSW, at 8:00 pm MDT on 24 April 2026, estimated intensity II (weak) in town. Every earthquake near Hamilton
This page: a magnitude 1.6 earthquake was recorded 33 km (21 mi) northeast of Hamilton, MT, at 6:44 am MDT on 16 April 2021 (12:44 UTC), 2.9 km deep.
USGS: Western Montana
53 km (33 mi) SSE of Missoula, MT
- When
- 6:44 am MDT on 16 April 2021 ()
- Where
- 33 km (21 mi) northeast of Hamilton, MT · earthquakes near Hamilton
- Montana today
- every earthquake in Montana in the last 24 hours
- Magnitude
- M 1.6 (ml)
- Depth
- 2.9 km below the surface
- Felt
- no reports yet
- Nearest
- Granite County, 29 km E
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2035 days ago
Earthquake alerts for Hamilton, 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. In Hamilton, 33 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.
Earthquakes near other towns within 30 km: Stevensville.
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.
- Mineral, Virginia 2011 M 5.8 1,900,000× the energy of this one
- Magna, Utah 2020 M 5.7 1,400,000× the energy of this one
- Around the size people start to feel M 3.0 120× the energy of this one
- 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 since 1900 lists no earthquake of M5 or more within 50 km.
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 46.4190, -113.8062. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Granite County, MT | 29 km (18 mi) | E | earthquakes near Granite County |
| Ravalli County, MT | 44 km (28 mi) | SSW | earthquakes near Ravalli County |
| Deer Lodge County, MT | 63 km (39 mi) | SE | earthquakes near Deer Lodge County |
| Missoula County, MT | 68 km (42 mi) | N | earthquakes near Missoula County |
| Powell County, MT | 82 km (51 mi) | NE | earthquakes near Powell County |
| Silver Bow County, MT | 106 km (66 mi) | ESE | earthquakes near Silver Bow County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
11 earthquakes have been recorded within 50 km since this one.
- 1.6 6 km N of Charlos Heights, Montana
- 1.8 2 km S of Turah, Montana
- 1.6 10 km WSW of Drummond, Montana
- 2.2 Idaho-Montana border region
- 1.9 Idaho-Montana border region
- 1.7 15 km WSW of Drummond, Montana
- 1.9 19 km W of Drummond, Montana
- 1.8 18 km W of Drummond, Montana
- 1.5 18 km W of Drummond, Montana
- 2.4 18 km W of Drummond, Montana
- 2.2 18 km W of Drummond, 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.