QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5ml

Earthquake near Butte, AK

No earthquake was likely felt in Butte in the 24 hours to 7:56 am AKST (16:56 UTC). The last one was M 4.4, 112 km (69 mi) ENE, at 11:11 am AKDT on 30 October 2026, estimated intensity II (weak) in town; 54 felt reports to USGS. Every earthquake near Butte

This page: a magnitude 1.5 earthquake was recorded 50 km (31 mi) east-northeast of Butte, AK, at 2:45 pm AKDT on 27 May 2026 (22:45 UTC), 14 km deep.

USGS: 24 km SE of Chickaloon, Alaska

2:45 pm AKDT, May 27, 2026 · · 14 km deep · released about 5.4 lb of TNT

Every earthquake near Butte Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Anchorage Municipality 81 kmMatanuska-Susitna Borough 100 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
2:45 pm AKDT on 27 May 2026 ()
Where
50 km (31 mi) east-northeast of Butte, AK · earthquakes near Butte
Magnitude
M 1.5 (ml)
Depth
14 km below the surface
Felt
no reports yet
Nearest
Anchorage Municipality, 81 km SW
Nearest mapped fault
Castle Mountain fault, 23 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 170 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 Butte, 50 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.

How big was it?

This earthquake released about 5.4 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 2,800,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 2,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 180× the energy of this one
  4. This earthquake M 1.5 about 5.4 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 4.8 on 2022-10-06 — about 89,000 times the energy of this one.

Before 2016, the USGS record lists 10 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.8 31 km SSW of Glacier View, Alaska · 22 km SE of this epicentre
  2. 6.4 23 km S of Glacier View, Alaska · 24 km ESE of this epicentre
  3. 6.4 37 km SSE of Glacier View, Alaska · 41 km ESE of this epicentre
  4. 5.9 15 km N of Glacier View, Alaska · 40 km NNE of this epicentre
  5. 5.9 42 km S of Glacier View, Alaska · 37 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 61.6450, -148.1160. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Anchorage Municipality, AK 81 km (50 mi) SW earthquakes near Anchorage Municipality
Matanuska-Susitna Borough, AK 100 km (62 mi) NW earthquakes near Matanuska-Susitna Borough

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

Aftershocks so far

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

  1. 1.5 57 km S of Glacier View, Alaska
  2. 3.5 31 km SE of Chickaloon, Alaska
  3. 1.8 16 km NNW of Glacier View, Alaska
  4. 1.8 23 km SSE of Chickaloon, Alaska
  5. 1.5 15 km NNW of Glacier View, Alaska
  6. 1.5 17 km W of Glacier View, Alaska
  7. 1.7 13 km W of Glacier View, Alaska
  8. 1.5 44 km S of Glacier View, Alaska
  9. 1.6 42 km ESE of Knik River, Alaska
  10. 2.3 24 km N of Glacier View, Alaska
  11. 1.9 36 km NNE of Chickaloon, Alaska
  12. 1.6 23 km SE of Knik River, Alaska
  13. 1.7 15 km ESE of Knik River, Alaska
  14. 1.5 6 km ESE of Sutton-Alpine, Alaska
  15. 2.5 26 km SSE of Chickaloon, Alaska

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.