Earthquake · reviewed by a seismologist
M 2.2ml
Earthquake near Polson, MT
No earthquake was likely felt in Polson in the 24 hours to 1:25 pm MST (20:25 UTC). The last one was M 3.0, 32 km (20 mi) ENE, at 9:19 pm MDT on 14 March 2024, estimated intensity II (weak) in town; 1 felt report to USGS. Every earthquake near Polson
This page: a magnitude 2.2 earthquake was recorded 20 km (12 mi) east of Polson, MT, at 6:41 pm MDT on 22 July 2020 (00:41 UTC), 19 km deep.
USGS: 12 km ESE of Finley Point, Montana
- When
- 6:41 pm MDT on 22 July 2020 ()
- Where
- 20 km (12 mi) east of Polson, MT · earthquakes near Polson
- Montana today
- every earthquake in Montana in the last 24 hours
- Magnitude
- M 2.2 (ml)
- Depth
- 19 km below the surface
- Felt
- no reports yet
- Nearest
- Lake County, 16 km WSW
- Nearest mapped fault
- Mission fault, 8 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 2302 days ago
Earthquake alerts for Polson, MT
Get a notification in this browser when USGS records an earthquake near Polson, MT. 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 it was probably too small to be felt, even directly above it. In Polson, 20 km away, the estimate is intensity II (weak). 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: Pablo, Ronan.
How big was it?
This earthquake released about 60 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.2 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 250,000× the energy of this one
- Magna, Utah 2020 M 5.7 180,000× the energy of this one
- Around the size people start to feel M 3.0 16× the energy of this one
- This earthquake M 2.2 about 60 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 one earthquake of M5 or more within 50 km:
- 5.5 Western Montana · 33 km NNE 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 47.7122, -113.9015. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Lake County, MT | 16 km (10 mi) | WSW | earthquakes near Lake County |
| Flathead County, MT | 66 km (41 mi) | N | earthquakes near Flathead County |
| Missoula County, MT | 76 km (47 mi) | S | earthquakes near Missoula County |
| Sanders County, MT | 96 km (60 mi) | W | earthquakes near Sanders County |
| Mineral County, MT | 110 km (68 mi) | SW | earthquakes near Mineral County |
| Powell County, MT | 121 km (75 mi) | SE | earthquakes near Powell County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
55 earthquakes have been recorded within 50 km since this one.
- 1.7 20 km E of Finley Point, Montana
- 1.6 20 km E of Finley Point, Montana
- 1.6 20 km E of Finley Point, Montana
- 2.1 20 km E of Finley Point, Montana
- 1.8 17 km E of Condon, Montana
- 1.7 19 km E of Finley Point, Montana
- 1.6 16 km NNE of Condon, Montana
- 1.6 6 km SW of Woods Bay, Montana
- 1.7 1 km S of Woods Bay, Montana
- 2.1 6 km SW of Woods Bay, Montana
- 1.6 6 km SW of Woods Bay, Montana
- 1.8 14 km WNW of Condon, Montana
- 1.6 16 km WSW of Kerr, Montana
- 1.5 5 km NE of Saint Ignatius, Montana
- 2.1 27 km E of Swan Lake, 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.