QuakeIndex

Earthquake · reviewed by a seismologist

M 2.7ml

Earthquake near Big Timber, MT

No earthquake was likely felt in Big Timber in the 24 hours to 9:08 am MST (16:08 UTC). The last one was M 3.8, 51 km (32 mi) W, at 12:28 pm MST on 30 January 2023, estimated intensity II (weak) in town; 309 felt reports to USGS. Every earthquake near Big Timber

This page: a magnitude 2.7 earthquake was recorded 45 km (28 mi) northwest of Big Timber, MT, at 6:18 pm MDT on 3 November 2017 (00:18 UTC), 4.2 km deep. 1 person has reported feeling it to USGS.

USGS: 32 km NE of Wilsall, Montana

6:18 pm MDT, Nov 3, 2017 · · 4.2 km deep · released about 340 lb of TNT

10 km30 km60 km120 km N Sweet Grass County 48 kmWheatland County 51 kmMeagher County 67 kmPark County 79 kmStillwater County 91 kmGolden Valley County 91 kmBroadwater County 93 kmGallatin County 97 kmJudith Basin County 97 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
6:18 pm MDT on 3 November 2017 ()
Where
45 km (28 mi) northwest of Big Timber, MT · earthquakes near Big Timber
Montana today
every earthquake in Montana in the last 24 hours
Magnitude
M 2.7 (ml)
Depth
4.2 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Sweet Grass County, 48 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3214 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 25 km (16 mi) from the epicentre. In Big Timber, 45 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.

How big was it?

This earthquake released about 340 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 45,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 32,000× the energy of this one
  3. Around the size people start to feel M 3.0 2.8× the energy of this one
  4. This earthquake M 2.7 about 340 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 46.1574, -110.3124. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Sweet Grass County, MT 48 km (30 mi) SE earthquakes near Sweet Grass County
Wheatland County, MT 51 km (32 mi) NE earthquakes near Wheatland County
Meagher County, MT 67 km (41 mi) NW earthquakes near Meagher County
Park County, MT 79 km (49 mi) SSW earthquakes near Park County
Stillwater County, MT 91 km (56 mi) SE earthquakes near Stillwater County
Golden Valley County, MT 91 km (56 mi) ENE earthquakes near Golden Valley County

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

Aftershocks so far

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

  1. 1.8 23 km ENE of Wilsall, Montana
  2. 2.2 30 km ENE of Wilsall, Montana
  3. 1.9 23 km SE of White Sulphur Springs, 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.