QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7ml

Earthquake near Eielson Air Force Base, AK

USGS: 25 km NE of Harding-Birch Lakes, Alaska

8:40 pm AKDT, Apr 7, 2025 · · 7.3 km deep · released about 11 lb of TNT

Every earthquake near Eielson Air Force Base Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Fairbanks North Star Borough 23 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
8:40 pm AKDT on 7 April 2025 ()
Where
45 km (28 mi) ESE of Eielson Air Force Base, AK · earthquakes near Eielson Air Force Base
Magnitude
M 1.7 (ml)
Depth
7.3 km below the surface
Felt
1 report · strongest reported intensity III
Nearest
Fairbanks North Star Borough, 23 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 522 days ago

A magnitude 1.7 earthquake was recorded 45 km (28 mi) ESE of Eielson Air Force Base, AK, at 8:40 pm AKDT on 7 April 2025 (04:40 UTC). 1 person has reported feeling it to USGS. This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 11 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 1,400,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 89× the energy of this one
  4. This earthquake M 1.7 about 11 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. 7.1 Central Alaska · 33 km WNW 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 64.5128, -146.1855. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Fairbanks North Star Borough, AK 23 km (14 mi) NW earthquakes near Fairbanks North Star Borough

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

Aftershocks so far

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

  1. 1.7 23 km ENE of Harding-Birch Lakes, Alaska
  2. 0.8 15 km ENE of Salcha, Alaska
  3. 1.5 8 km NW of Harding-Birch Lakes, Alaska
  4. 1.8 37 km NE of Harding-Birch Lakes, Alaska
  5. 1.9 19 km E of Pleasant Valley, Alaska
  6. 1.5 8 km NE of Big Delta, Alaska
  7. 1.7 31 km ESE of Pleasant Valley, Alaska
  8. 2.3 32 km ESE of Pleasant Valley, Alaska
  9. 1.6 43 km E of Pleasant Valley, Alaska
  10. 1.6 16 km NNW of Whitestone, Alaska
  11. 3.0 8 km NW of Harding-Birch Lakes, Alaska
  12. 1.9 22 km ESE of Pleasant Valley, Alaska
  13. 1.6 8 km NW of Harding-Birch Lakes, Alaska
  14. 1.6 1 km SSE of Whitestone, Alaska
  15. 1.6 8 km NW of Harding-Birch Lakes, 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.