QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5ml

Earthquake near Ronan, MT

No earthquake was likely felt in Ronan in the 24 hours to 9:50 am MST (16:50 UTC). The last one was M 2.6, 20 km (12 mi) SE, at 4:57 am MST on 19 January 2026, estimated intensity II (weak) in town. Every earthquake near Ronan

This page: a magnitude 1.5 earthquake was recorded 21 km (13 mi) south-southeast of Ronan, MT, at 5:30 pm MDT on 11 June 2020 (23:30 UTC), 13 km deep.

USGS: 7 km ENE of Saint Ignatius, Montana

53 km (33 mi) N of Missoula, MT

5:30 pm MDT, Jun 11, 2020 · · 13 km deep · released about 6.2 lb of TNT

10 km30 km60 km120 km N Lake County 33 kmMissoula County 37 kmMineral County 85 kmSanders County 98 kmPowell County 100 kmFlathead County 105 kmGranite County 115 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
5:30 pm MDT on 11 June 2020 ()
Where
21 km (13 mi) south-southeast of Ronan, MT · earthquakes near Ronan
Montana today
every earthquake in Montana in the last 24 hours
Magnitude
M 1.5 (ml)
Depth
13 km below the surface
Felt
no reports yet
Nearest
Lake County, 33 km N
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 2344 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Ronan, 21 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: Pablo.

How big was it?

This earthquake released about 6.2 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,500,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,700,000× the energy of this one
  3. Around the size people start to feel M 3.0 150× the energy of this one
  4. This earthquake M 1.5 about 6.2 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 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 47.3530, -114.0147. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lake County, MT 33 km (20 mi) N earthquakes near Lake County
Missoula County, MT 37 km (23 mi) SSE earthquakes near Missoula County
Mineral County, MT 85 km (53 mi) WSW earthquakes near Mineral County
Sanders County, MT 98 km (61 mi) WNW earthquakes near Sanders County
Powell County, MT 100 km (62 mi) SE earthquakes near Powell County
Flathead County, MT 105 km (65 mi) N earthquakes near Flathead County

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

Aftershocks so far

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

  1. 1.7 2 km ENE of Alberton, Montana
  2. 2.2 2 km NE of Alberton, Montana
  3. 1.7 4 km WNW of Wye, Montana
  4. 2.6 13 km ESE of Kicking Horse, Montana
  5. 2.0 15 km ENE of Ronan, Montana
  6. 2.1 5 km WNW of Saint Ignatius, Montana
  7. 1.7 20 km E of Finley Point, Montana
  8. 1.6 20 km E of Finley Point, Montana
  9. 1.6 20 km E of Finley Point, Montana
  10. 2.1 20 km E of Finley Point, Montana
  11. 1.8 17 km E of Condon, Montana
  12. 1.7 19 km E of Finley Point, Montana
  13. 1.6 16 km NNE of Condon, Montana
  14. 1.8 14 km WNW of Condon, Montana
  15. 1.5 12 km SW of Seeley Lake, 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.