QuakeIndex

Earthquake · reviewed by a seismologist

M 3.9mwr

Earthquake near Lincoln, MT

No earthquake was likely felt in Lincoln in the 24 hours to 5:29 am MST (12:29 UTC). The last one was M 3.1, 40 km (25 mi) WNW, at 8:34 pm MDT on 4 October 2026, estimated intensity II (weak) in town; 4 felt reports to USGS. Every earthquake near Lincoln

This page: a magnitude 3.9 earthquake was recorded 13 km (8 mi) southeast of Lincoln, MT, at 4:18 pm MDT on 19 October 2017 (22:18 UTC), 3.9 km deep. 38 people have reported feeling it to USGS.

USGS: 12 km SE of Lincoln, Montana

4:18 pm MDT, Oct 19, 2017 · · 3.9 km deep · released about 11 tons of TNT

10 km30 km60 km120 km N Powell County 29 kmLewis and Clark County 29 kmGranite County 86 kmJefferson County 93 kmDeer Lodge County 99 kmBroadwater County 101 kmCascade County 103 kmMissoula County 103 kmTeton County 106 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
4:18 pm MDT on 19 October 2017 ()
Where
13 km (8 mi) southeast of Lincoln, MT · earthquakes near Lincoln
Montana today
every earthquake in Montana in the last 24 hours
Magnitude
M 3.9 (mwr)
Depth
3.9 km below the surface
Felt
38 reports · strongest reported intensity III
Measured shaking
intensity IV (ShakeMap)
USGS impact alert
green
Nearest
Powell County, 29 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1607 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 89 km (55 mi) from the epicentre. In Lincoln, 13 km away, the estimate is intensity IV (light). 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.

Likely felt in: Lincoln 13 km, intensity IV. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 11 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.9 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 16,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 710× the energy of this one
  3. Magna, Utah 2020 M 5.7 500× the energy of this one
  4. This earthquake M 3.9 about 11 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 22× more

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 5.8 on 2017-07-06 — about 710 times the energy of this one.

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 46.8848, -112.5524. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Powell County, MT 29 km (18 mi) W earthquakes near Powell County
Lewis and Clark County, MT 29 km (18 mi) NNE earthquakes near Lewis and Clark County
Granite County, MT 86 km (54 mi) SW earthquakes near Granite County
Jefferson County, MT 93 km (58 mi) SSE earthquakes near Jefferson County
Deer Lodge County, MT 99 km (61 mi) SSW earthquakes near Deer Lodge County
Broadwater County, MT 101 km (63 mi) SE earthquakes near Broadwater 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. 1.6 15 km SE of Lincoln, Montana
  2. 1.6 14 km ESE of Lincoln, Montana
  3. 1.6 12 km ESE of Lincoln, Montana
  4. 2.6 14 km ESE of Lincoln, Montana
  5. 3.0 18 km ESE of Lincoln, Montana
  6. 2.6 18 km NW of Marysville, Montana
  7. 1.5 16 km SE of Lincoln, Montana
  8. 1.7 19 km NNW of Marysville, Montana
  9. 1.6 14 km SE of Lincoln, Montana
  10. 1.6 14 km ESE of Lincoln, Montana
  11. 1.5 Western Montana
  12. 1.6 13 km ESE of Lincoln, Montana
  13. 1.8 20 km E of Lincoln, Montana
  14. 1.7 13 km ESE of Lincoln, Montana
  15. 1.9 13 km ESE of Lincoln, 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.