QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9ml

Earthquake near Dillon, MT

No earthquake was likely felt in Dillon in the 24 hours to 10:26 pm MST (05:26 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 1.9 earthquake was recorded 24 km (15 mi) south-southeast of Dillon, MT, at 2:47 pm MDT on 18 June 2023 (20:47 UTC), 5.0 km deep.

USGS: 23 km SSE of Dillon, Montana

2:47 pm MDT, Jun 18, 2023 · · 5.0 km deep · released about 24 lb of TNT

10 km30 km60 km120 km N Beaverhead County 31 kmMadison County 59 kmClark County 82 kmSilver Bow County 99 kmLemhi County 107 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
2:47 pm MDT on 18 June 2023 ()
Where
24 km (15 mi) south-southeast of Dillon, MT · earthquakes near Dillon
Montana today
every earthquake in Montana in the last 24 hours
Magnitude
M 1.9 (ml)
Depth
5.0 km below the surface
Felt
no reports yet
Nearest
Beaverhead County, 31 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1241 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 14 km (9 mi) from the epicentre. In Dillon, 24 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 24 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 640,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 450,000× the energy of this one
  3. Around the size people start to feel M 3.0 40× the energy of this one
  4. This earthquake M 1.9 about 24 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 10,000 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 · 40 km N of this epicentre
  2. 5.1 19 km NW of Lima, Montana · 32 km SSW of this epicentre
  3. 5.1 22 km NW of Lima, Montana · 33 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 45.0148, -112.5292. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Beaverhead County, MT 31 km (20 mi) WNW earthquakes near Beaverhead County
Madison County, MT 59 km (37 mi) NE earthquakes near Madison County
Clark County, ID 82 km (51 mi) S earthquakes near Clark County
Silver Bow County, MT 99 km (61 mi) N earthquakes near Silver Bow County
Lemhi County, ID 107 km (67 mi) W earthquakes near Lemhi County
Gallatin County, MT 121 km (75 mi) ENE earthquakes near Gallatin County

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

Aftershocks so far

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

  1. 1.5 3 km SE of Lima, Montana
  2. 2.5 11 km NNE of Dillon, Montana
  3. 2.6 6 km E of Lima, Montana
  4. 2.4 Idaho-Montana border region
  5. 1.8 Idaho-Montana border region
  6. 2.6 8 km ESE of Lima, Montana
  7. 1.5 14 km NNE of Dillon, Montana
  8. 2.4 1 km WSW of Lima, Montana
  9. 1.6 18 km ESE of Dillon, Montana
  10. 2.2 8 km E of Lima, Montana
  11. 1.7 28 km WNW of Dillon, Montana
  12. 1.6 3 km SSE of Lima, Montana
  13. 1.7 3 km SSE of Lima, Montana
  14. 2.1 3 km SSE of Lima, Montana
  15. 2.3 3 km SSE of Lima, 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.