QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1ml

Earthquake near Plains, MT

No earthquake was likely felt in Plains in the 24 hours to 9:12 am MST (16:12 UTC). The last one was M 1.8, 6 km (4 mi) NNW, at 6:42 am MDT on 9 July 2023, estimated intensity II (weak) in town. Every earthquake near Plains

This page: a magnitude 3.1 earthquake was recorded 18 km (11 mi) east-southeast of Plains, MT, at 5:12 pm MDT on 7 July 2019 (23:12 UTC), 5.0 km deep. 5 people have reported feeling it to USGS.

USGS: 12 km ENE of Paradise, Montana

5:12 pm MDT, Jul 7, 2019 · · 5.0 km deep · released about 1,300 lb of TNT

10 km30 km60 km120 km N Mineral County 46 kmLake County 49 kmSanders County 55 kmMissoula County 72 kmShoshone County 93 kmFlathead County 107 kmClearwater County 113 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
5:12 pm MDT on 7 July 2019 ()
Where
18 km (11 mi) east-southeast of Plains, MT · earthquakes near Plains
Montana today
every earthquake in Montana in the last 24 hours
Magnitude
M 3.1 (ml)
Depth
5.0 km below the surface
Felt
5 reports · strongest reported intensity III
Nearest
Mineral County, 46 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2409 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 41 km (25 mi) from the epicentre. In Plains, 18 km away, the estimate is intensity III (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 1,300 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 250,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,900× the energy of this one
  4. This earthquake M 3.1 about 1,300 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.4× 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

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 47.4218, -114.6488. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Mineral County, MT 46 km (29 mi) SW earthquakes near Mineral County
Lake County, MT 49 km (30 mi) ENE earthquakes near Lake County
Sanders County, MT 55 km (34 mi) NW earthquakes near Sanders County
Missoula County, MT 72 km (45 mi) SE earthquakes near Missoula County
Shoshone County, ID 93 km (58 mi) W earthquakes near Shoshone County
Flathead County, MT 107 km (66 mi) NNE earthquakes near Flathead County

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

Aftershocks so far

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

  1. 1.4 16 km NW of Old Agency, Montana
  2. 1.9 2 km NNE of Alberton, Montana
  3. 1.7 2 km ENE of Alberton, Montana
  4. 2.2 2 km NE of Alberton, Montana
  5. 2.1 5 km WNW of Saint Ignatius, Montana
  6. 2.2 1 km SE of Alberton, Montana
  7. 1.6 16 km WSW of Kerr, Montana
  8. 2.0 17 km W of Niarada, Montana
  9. 1.6 4 km W of Ravalli, Montana
  10. 1.6 4 km NW of Niarada, Montana
  11. 1.8 6 km NNW of Plains, Montana
  12. 1.6 Western Montana
  13. 2.5 18 km WNW of Dixon, Montana
  14. 3.7 3 km NE of Ravalli, Montana
  15. 3.2 2 km ESE of Ravalli, 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.