QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5ml

Earthquake near Kalispell, MT

No earthquake was likely felt in Kalispell in the 24 hours to 9:45 am MST (16:45 UTC). The last one was M 2.6, 22 km (13 mi) NNW, at 1:53 am MST on 1 March 2021, estimated intensity II (weak) in town. Every earthquake near Kalispell

This page: a magnitude 2.5 earthquake was recorded 36 km (22 mi) south-southeast of Kalispell, MT, at 11:54 am MDT on 27 August 2019 (17:54 UTC), 10 km deep.

USGS: 3 km W of Bear Dance, Montana

11:54 am MDT, Aug 27, 2019 · · 10 km deep · released about 170 lb of TNT

10 km30 km60 km120 km N Lake County 31 kmFlathead County 42 kmSanders County 84 kmMissoula County 100 kmMineral County 116 kmGlacier County 119 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
11:54 am MDT on 27 August 2019 ()
Where
36 km (22 mi) south-southeast of Kalispell, MT · earthquakes near Kalispell
Montana today
every earthquake in Montana in the last 24 hours
Magnitude
M 2.5 (ml)
Depth
10 km below the surface
Felt
no reports yet
Nearest
Lake County, 31 km S
Nearest mapped fault
Mission fault, under 1 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 2555 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 20 km (12 mi) from the epicentre. In Kalispell, 36 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.

Earthquakes near other towns within 30 km: Lakeside, Bigfork, Somers, Polson.

How big was it?

This earthquake released about 170 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 89,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 63,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.6× the energy of this one
  4. This earthquake M 2.5 about 170 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

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

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 5.5 Western Montana · 23 km ENE 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 47.9174, -114.0784. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lake County, MT 31 km (19 mi) S earthquakes near Lake County
Flathead County, MT 42 km (26 mi) N earthquakes near Flathead County
Sanders County, MT 84 km (52 mi) WSW earthquakes near Sanders County
Missoula County, MT 100 km (62 mi) S earthquakes near Missoula County
Mineral County, MT 116 km (72 mi) SW earthquakes near Mineral County
Glacier County, MT 119 km (74 mi) NE earthquakes near Glacier County

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

Aftershocks so far

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

  1. 1.6 16 km WSW of Kerr, Montana
  2. 2.3 10 km NNW of Swan Lake, Montana
  3. 1.7 15 km NNE of Bigfork, Montana
  4. 3.0 17 km SSE of Swan Lake, Montana
  5. 1.6 9 km ENE of Ronan, Montana
  6. 1.7 5 km ESE of Lakeside, Montana
  7. 1.5 8 km ESE of Woods Bay, Montana
  8. 2.1 18 km SSE of Swan Lake, Montana
  9. 1.6 3 km NNE of Somers, Montana
  10. 1.5 11 km ENE of Ronan, Montana
  11. 1.6 Western Montana
  12. 1.6 Western Montana
  13. 2.1 8 km NNW of Bigfork, Montana
  14. 1.9 21 km NNW of Condon, Montana
  15. 2.9 4 km N of Elmo, 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.