QuakeIndex

Earthquake · reviewed by a seismologist

M 2.6ml

8 km ESE of Lima, Montana

Yes. A magnitude 2.6 earthquake was recorded 8 km ESE of Lima, Montana, at 4:28 am MDT on 4 November 2023 (10:28 UTC), 12 km deep.

· 12 km deep · released about 240 lb of TNT

10 km30 km60 km120 km N Clark County 38 kmBeaverhead County 66 kmMadison County 90 kmFremont County 91 kmJefferson County 92 kmMadison County 113 kmLemhi County 116 kmButte County 118 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
Montana today
every earthquake in Montana in the last 24 hours
Magnitude
M 2.6 (ml)
Depth
12 km below the surface
Felt
no reports yet
Nearest
Clark County, 38 km SSE
Nearest mapped fault
Red Rock fault, 10 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 1037 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. 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 240 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 63,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 45,000× the energy of this one
  3. Around the size people start to feel M 3.0 4× the energy of this one
  4. This earthquake M 2.6 about 240 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 1,000 times the energy of this one.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 5.1 19 km NW of Lima, Montana · 27 km NW of this epicentre
  2. 5.1 22 km NW of Lima, Montana · 30 km NW 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 44.6196, -112.4832. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Clark County, ID 38 km (24 mi) SSE earthquakes near Clark County
Beaverhead County, MT 66 km (41 mi) NNW earthquakes near Beaverhead County
Madison County, MT 90 km (56 mi) NNE earthquakes near Madison County
Fremont County, ID 91 km (57 mi) ESE earthquakes near Fremont County
Jefferson County, ID 92 km (57 mi) S earthquakes near Jefferson County
Madison County, ID 113 km (71 mi) SE earthquakes near Madison County

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

Aftershocks so far

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

  1. 2.3 24 km N of Spencer, Idaho
  2. 1.9 23 km N of Spencer, Idaho
  3. 2.2 23 km N of Spencer, Idaho
  4. 2.0 23 km N of Spencer, Idaho
  5. 1.8 23 km N of Spencer, Idaho
  6. 1.7 33 km NW of Lima, Montana
  7. 1.8 34 km NW of Lima, Montana
  8. 1.8 33 km NW of Lima, Montana
  9. 1.7 31 km NNE of Spencer, Idaho
  10. 1.9 2 km SSE of Lima, Montana
  11. 2.3 2 km SE of Lima, Montana
  12. 1.5 11 km SE of Lima, Montana
  13. 1.6 11 km SE of Lima, Montana
  14. 1.9 11 km SE of Lima, Montana
  15. 1.8 40 km NNE of Spencer, Idaho

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.