QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6ml

Earthquake near Dillon, MT

No earthquake was likely felt in Dillon in the 24 hours to 4:48 pm MST (23:48 UTC). The last one was M 2.0, 14 km (9 mi) N, at 2:45 pm MDT on 7 May 2026, estimated intensity II (weak) in town. Every earthquake near Dillon

This page: a magnitude 1.6 earthquake was recorded 16 km (10 mi) south-southwest of Dillon, MT, at 4:36 pm MDT on 28 August 2025 (22:36 UTC), 12 km deep.

USGS: 16 km SSW of Dillon, Montana

4:36 pm MDT, Aug 28, 2025 · · 12 km deep · released about 8.7 lb of TNT

10 km30 km60 km120 km N Beaverhead County 14 kmMadison County 69 kmSilver Bow County 90 kmLemhi County 92 kmClark County 93 kmDeer Lodge County 117 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
4:36 pm MDT on 28 August 2025 ()
Where
16 km (10 mi) south-southwest of Dillon, MT · earthquakes near Dillon
Montana today
every earthquake in Montana in the last 24 hours
Magnitude
M 1.6 (ml)
Depth
12 km below the surface
Felt
no reports yet
Nearest
Beaverhead County, 14 km WNW
Nearest mapped fault
Red Rock fault, 20 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 440 days ago

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 Dillon, 16 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 8.7 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.

  1. Mineral, Virginia 2011 M 5.8 1,700,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,200,000× the energy of this one
  3. Around the size people start to feel M 3.0 110× the energy of this one
  4. This earthquake M 1.6 about 8.7 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 4.6 on 2019-04-09 — about 28,000 times the energy of this one.

Before 2016, the USGS record lists 3 earthquakes of M5 or more within 50 km:

  1. 5.6 16 km N of Dillon, Montana · 32 km NNE of this epicentre
  2. 5.1 19 km NW of Lima, Montana · 35 km S of this epicentre
  3. 5.1 22 km NW of Lima, Montana · 34 km S 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 45.0847, -112.7320. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Beaverhead County, MT 14 km (9 mi) WNW earthquakes near Beaverhead County
Madison County, MT 69 km (43 mi) ENE earthquakes near Madison County
Silver Bow County, MT 90 km (56 mi) N earthquakes near Silver Bow County
Lemhi County, ID 92 km (57 mi) W earthquakes near Lemhi County
Clark County, ID 93 km (58 mi) SSE earthquakes near Clark County
Deer Lodge County, MT 117 km (73 mi) NNW earthquakes near Deer Lodge County

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

Aftershocks so far

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

  1. 1.4 19 km N of Dillon, Montana
  2. 1.3 35 km NW of Lima, Montana
  3. 1.0 11 km WSW of Sheridan, Montana
  4. 1.7 33 km NW of Lima, Montana
  5. 1.9 19 km NNE of Dillon, Montana
  6. 2.0 15 km NNE of Dillon, Montana
  7. 1.0 3 km NW of Lima, Montana
  8. 2.1 26 km SE of Dillon, Montana
  9. 2.8 19 km NE of Lima, Montana
  10. 2.0 13 km N of Dillon, Montana
  11. 1.6 11 km NNE of Dillon, Montana
  12. 2.5 9 km NNE of Dillon, Montana
  13. 1.5 14 km NNE of Dillon, Montana
  14. 2.5 10 km NNE of Dillon, Montana
  15. 1.8 27 km SW of Dillon, 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.