QuakeIndex

quarry blast · reviewed by a seismologist

M 1.7ml

Earthquake near Bozeman, MT

No earthquake was likely felt in Bozeman in the 24 hours to 1:23 pm MST (20:23 UTC). The last one was M 3.0, 17 km (10 mi) NW, at 7:42 am MDT on 1 June 2024, estimated intensity II (weak) in town; 20 felt reports to USGS. Every earthquake near Bozeman

No: USGS classifies this as a quarry blast, not an earthquake. A magnitude 1.7 quarry blast was recorded 39 km (24 mi) northwest of Bozeman, MT, at 2:12 pm MDT on 26 July 2022 (20:12 UTC), less than 1 km deep.

USGS: 3 km NNE of Logan, Montana

38 km (24 mi) NW of Bozeman, MT

2:12 pm MDT, Jul 26, 2022 · · -2.0 km deep · released about 10 lb of TNT

10 km30 km60 km120 km N Broadwater County 47 kmGallatin County 48 kmJefferson County 55 kmMadison County 76 kmMeagher County 84 kmPark County 85 kmSilver Bow County 96 kmSweet Grass 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
2:12 pm MDT on 26 July 2022 ()
Where
39 km (24 mi) northwest of Bozeman, MT · earthquakes near Bozeman
Montana today
every earthquake in Montana in the last 24 hours
Magnitude
M 1.7 (ml)
Depth
-2.0 km below the surface
Felt
no reports yet
Nearest
Broadwater County, 47 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1568 days ago

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

At this magnitude and depth, people at rest would likely notice it out to about 12 km (7 mi) from the epicentre. In Bozeman, 39 km away, the estimate is intensity I (not felt). 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: Manhattan 9 km, intensity II · Three Forks 11 km, intensity II. Estimated for each town centre; each link is that town's own record.

USGS catalogues this as quarry blast, not an earthquake.

How big was it?

This earthquake released about 10 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 1,500,000× 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 95× the energy of this one
  4. This earthquake M 1.7 about 10 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

The largest earthquake within 50 km since 2016 was M 4.2 on 2019-08-16 — about 6,000 times the energy of this one.

Before 2016, the USGS record lists 6 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.6 The 1925 Clarkston Valley, Montana Earthquake · 20 km NNW of this epicentre
  2. 6.4 Clarkston Valley, Montana (Aftershock) · 20 km NNW of this epicentre
  3. 5.5 Clarkston Valley, Montana (Aftershock) · 20 km NNW of this epicentre
  4. 5.5 Clarkston Valley, Montana (Aftershock) · 20 km NNW of this epicentre
  5. 5.5 Clarkston Valley, Montana (Aftershock) · 20 km NNW 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 45.9108, -111.4182. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Broadwater County, MT 47 km (29 mi) N earthquakes near Broadwater County
Gallatin County, MT 48 km (30 mi) SSE earthquakes near Gallatin County
Jefferson County, MT 55 km (34 mi) WNW earthquakes near Jefferson County
Madison County, MT 76 km (47 mi) SSW earthquakes near Madison County
Meagher County, MT 84 km (52 mi) NNE earthquakes near Meagher County
Park County, MT 85 km (53 mi) SE earthquakes near Park County

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

Aftershocks so far

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

  1. 1.6 6 km NW of Logan, Montana
  2. 1.7 7 km W of Townsend, Montana
  3. 2.0 7 km WSW of Townsend, Montana
  4. 1.8 8 km W of Townsend, Montana
  5. 1.7 9 km WSW of Townsend, Montana
  6. 1.9 6 km WSW of Townsend, Montana
  7. 2.2 10 km WNW of Radersburg, Montana
  8. 2.5 12 km WNW of Radersburg, Montana
  9. 2.0 7 km W of Townsend, Montana
  10. 1.6 11 km NNW of Pony, Montana
  11. 1.6 6 km W of Townsend, Montana
  12. 1.5 7 km W of Townsend, Montana
  13. 1.9 5 km WSW of Ponderosa Pines, Montana
  14. 1.5 8 km WSW of Townsend, Montana
  15. 2.0 5 km NNW of Logan, 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.