QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5ml

Earthquake near Townsend, MT

No earthquake was likely felt in Townsend in the 24 hours to 7:11 am MST (14:11 UTC). The last one was M 1.7, 9 km (5 mi) W, at 2:32 pm MDT on 15 October 2026, estimated intensity II (weak) in town. Every earthquake near Townsend

This page: a magnitude 2.5 earthquake was recorded 14 km (8 mi) east-southeast of Townsend, MT, at 2:57 pm MST on 25 January 2020 (21:57 UTC), 5.0 km deep. 3 people have reported feeling it to USGS.

USGS: 10 km NNE of Toston, Montana

2:57 pm MST, Jan 25, 2020 · · 5.0 km deep · released about 170 lb of TNT

Every earthquake near Townsend Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Broadwater County 13 kmMeagher County 50 kmJefferson County 55 kmGallatin County 83 kmSilver Bow County 107 kmPark County 109 kmMadison County 112 kmCascade County 118 kmJudith Basin County 119 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
2:57 pm MST on 25 January 2020 ()
Where
14 km (8 mi) east-southeast of Townsend, MT · earthquakes near Townsend
Montana today
every earthquake in Montana in the last 24 hours
Magnitude
M 2.5 (ml)
Depth
5.0 km below the surface
Felt
3 reports · strongest reported intensity III
Nearest
Broadwater County, 13 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2405 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 21 km (13 mi) from the epicentre. In Townsend, 14 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.

Likely felt in: Townsend 14 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 170 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 89,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 63,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.6× the energy of this one
  4. This earthquake M 2.5 about 170 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

The largest earthquake within 50 km since 2016 was M 4.2 on 2019-08-16 — about 350 times the energy of this one.

Before 2016, the USGS record lists 8 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.6 The 1925 Clarkston Valley, Montana Earthquake · 22 km SSW of this epicentre
  2. 6.4 Clarkston Valley, Montana (Aftershock) · 22 km SSW of this epicentre
  3. 6.1 The 1935 Helena, Montana Earthquakes (Mainshock) · 43 km NNW of this epicentre
  4. 5.9 The 1935 Helena, Montana Earthquakes (Largest Aftershock) · 49 km NW of this epicentre
  5. 5.5 Clarkston Valley, Montana (Aftershock) · 22 km SSW 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 46.2547, -111.3709. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Broadwater County, MT 13 km (8 mi) NW earthquakes near Broadwater County
Meagher County, MT 50 km (31 mi) NE earthquakes near Meagher County
Jefferson County, MT 55 km (34 mi) WSW earthquakes near Jefferson County
Gallatin County, MT 83 km (52 mi) S earthquakes near Gallatin County
Silver Bow County, MT 107 km (67 mi) WSW earthquakes near Silver Bow County
Park County, MT 109 km (68 mi) SE earthquakes near Park County

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

59 earthquakes have been recorded within 50 km since this one.

  1. 2.1 1 km SSE of Townsend, Montana
  2. 1.6 6 km N of Radersburg, Montana
  3. 1.5 7 km ENE of Townsend, Montana
  4. 1.6 8 km ENE of Townsend, Montana
  5. 1.8 7 km W of Townsend, Montana
  6. 2.2 6 km NNE of Manhattan, Montana
  7. 1.9 7 km SW of Radersburg, Montana
  8. 1.7 7 km SW of Radersburg, Montana
  9. 1.6 5 km NE of Logan, Montana
  10. 1.5 22 km SW of Radersburg, Montana
  11. 1.7 10 km WSW of Townsend, Montana
  12. 1.6 8 km WSW of Townsend, Montana
  13. 2.1 6 km NNE of Manhattan, Montana
  14. 2.0 4 km N of Logan, Montana
  15. 1.6 4 km NNW of Logan, 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

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.