QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1ml

Earthquake near Whitehall, MT

No earthquake was likely felt in Whitehall in the 24 hours to 2:06 pm MDT (20:06 UTC). The last one was M 2.9, 26 km (16 mi) SSW, at 4:22 pm MDT on 6 June 2026, estimated intensity II (weak) in town; 2 felt reports to USGS. Every earthquake near Whitehall

This page: a magnitude 2.1 earthquake was recorded 29 km (18 mi) south of Whitehall, MT, at 9:31 am MDT on 16 October 2026 (15:31 UTC), 4.2 km deep.

USGS: 15 km ENE of Twin Bridges, Montana

9:31 am MDT, Oct 16, 2026 · · 4.2 km deep · released about 49 lb of TNT

10 km30 km60 km120 km N Madison County 37 kmSilver Bow County 51 kmJefferson County 58 kmGallatin County 78 kmBeaverhead County 78 kmDeer Lodge County 94 kmBroadwater County 95 km
Distance rings around the epicentre, with the nearest towns at their true direction. Not a shaking map — see the USGS ShakeMap for that.
When
9:31 am MDT on 16 October 2026 ()
Where
29 km (18 mi) south of Whitehall, MT · earthquakes near Whitehall
Montana today
every earthquake in Montana in the last 24 hours
Magnitude
M 2.1 (ml)
Depth
4.2 km below the surface
Felt
no reports yet
Nearest
Madison County, 37 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 4 days ago

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 17 km (11 mi) from the epicentre. In Whitehall, 29 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 49 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 310,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 220,000× the energy of this one
  3. Around the size people start to feel M 3.0 19× the energy of this one
  4. This earthquake M 2.1 about 49 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 4.1 on 2024-10-07 — about 870 times the energy of this one.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 5.6 16 km N of Dillon, Montana · 45 km SW 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 45.6083, -112.1518. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Madison County, MT 37 km (23 mi) SSE earthquakes near Madison County
Silver Bow County, MT 51 km (32 mi) NW earthquakes near Silver Bow County
Jefferson County, MT 58 km (36 mi) N earthquakes near Jefferson County
Gallatin County, MT 78 km (48 mi) E earthquakes near Gallatin County
Beaverhead County, MT 78 km (49 mi) SW earthquakes near Beaverhead County
Deer Lodge County, MT 94 km (58 mi) NW earthquakes near Deer Lodge County

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

Aftershocks so far

No further earthquakes have been recorded within 50 km since this one.

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.