QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7ml

Earthquake near Bigfork, MT

USGS: 13 km N of Bigfork, Montana

10:14 pm MST, Feb 16, 2018 · · 5.8 km deep · released about 9.6 lb of TNT

10 km30 km60 km120 km N Flathead County 13 kmLake County 60 kmSanders County 97 kmGlacier County 97 kmLincoln County 112 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
10:14 pm MST on 16 February 2018 ()
Where
13 km (8 mi) N of Bigfork, MT · earthquakes near Bigfork
Magnitude
M 1.7 (ml)
Depth
5.8 km below the surface
Felt
no reports yet
Nearest
Flathead County, 13 km N
Nearest mapped fault
Mission 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 3146 days ago

A magnitude 1.7 earthquake was recorded 13 km (8 mi) N of Bigfork, MT, at 10:14 pm MST on 16 February 2018 (05:14 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

Earthquakes near other towns within 30 km: Somers, Evergreen, Kalispell, Lakeside, Columbia Falls.

How big was it?

This earthquake released about 9.6 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,100,000× the energy of this one
  3. Around the size people start to feel M 3.0 99× the energy of this one
  4. This earthquake M 1.7 about 9.6 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 · 27 km SE 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 48.1803, -114.0473. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Flathead County, MT 13 km (8 mi) N earthquakes near Flathead County
Lake County, MT 60 km (37 mi) S earthquakes near Lake County
Sanders County, MT 97 km (60 mi) WSW earthquakes near Sanders County
Glacier County, MT 97 km (61 mi) NE earthquakes near Glacier County
Lincoln County, MT 112 km (70 mi) WNW earthquakes near Lincoln County
Mineral County, MT 140 km (87 mi) SW earthquakes near Mineral County

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

Aftershocks so far

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

  1. 1.6 6 km SW of Woods Bay, Montana
  2. 2.2 7 km WNW of Lake Mary Ronan, Montana
  3. 1.7 7 km WNW of Lake Mary Ronan, Montana
  4. 1.8 6 km WNW of Lake Mary Ronan, Montana
  5. 1.7 30 km ESE of Martin City, Montana
  6. 2.5 24 km E of Swan Lake, Montana
  7. 2.3 10 km NNW of Swan Lake, Montana
  8. 1.7 15 km NNE of Bigfork, Montana
  9. 3.0 17 km SSE of Swan Lake, Montana
  10. 1.7 5 km ESE of Lakeside, Montana
  11. 1.5 8 km ESE of Woods Bay, Montana
  12. 1.6 3 km NNE of Somers, Montana
  13. 2.0 1 km ENE of Columbia Falls, Montana
  14. 1.6 Western Montana
  15. 2.1 8 km NNW of Bigfork, 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.