QuakeIndex

Earthquake · reviewed by a seismologist

M 2.4ml

Earthquake near Palmer, AK

No earthquake was likely felt in Palmer in the 24 hours to 1:50 am AKST (10:50 UTC). The last one was M 4.4, 114 km (71 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 Palmer

This page: a magnitude 2.4 earthquake was recorded 49 km (30 mi) east-northeast of Palmer, AK, at 9:02 pm AKDT on 18 August 2025 (05:02 UTC), 21 km deep.

USGS: 8 km E of Chickaloon, Alaska

9:02 pm AKDT, Aug 18, 2025 · · 21 km deep · released about 120 lb of TNT

Every earthquake near Palmer Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Matanuska-Susitna Borough 81 kmAnchorage Municipality 87 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
9:02 pm AKDT on 18 August 2025 ()
Where
49 km (30 mi) east-northeast of Palmer, AK · earthquakes near Palmer
Magnitude
M 2.4 (ml)
Depth
21 km below the surface
Felt
no reports yet
Nearest
Matanuska-Susitna Borough, 81 km NW
Nearest mapped fault
Castle Mountain fault, 8 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 374 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 2 km (1 mi) from the epicentre. In Palmer, 49 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.

How big was it?

This earthquake released about 120 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 130,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 89,000× the energy of this one
  3. Around the size people start to feel M 3.0 7.9× the energy of this one
  4. This earthquake M 2.4 about 120 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 4.6 on 2018-01-27 — about 2,000 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. 6.8 31 km SSW of Glacier View, Alaska · 41 km SE of this epicentre
  2. 6.4 23 km S of Glacier View, Alaska · 40 km SE of this epicentre
  3. 5.9 15 km N of Glacier View, Alaska · 35 km ENE of this epicentre
  4. 5.8 14 km NNE of Fishhook, Alaska · 43 km W of this epicentre
  5. 5.1 23 km S of Glacier View, Alaska · 43 km ESE 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 61.8029, -148.2979. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Matanuska-Susitna Borough, AK 81 km (50 mi) NW earthquakes near Matanuska-Susitna Borough
Anchorage Municipality, AK 87 km (54 mi) SW earthquakes near Anchorage Municipality

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

Aftershocks so far

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

  1. 1.6 36 km NNW of Chickaloon, Alaska
  2. 1.6 30 km SSE of Chickaloon, Alaska
  3. 1.8 9 km ENE of Knik River, Alaska
  4. 1.8 35 km SSE of Chickaloon, Alaska
  5. 1.6 8 km SSW of Chickaloon, Alaska
  6. 1.5 19 km ESE of Chickaloon, Alaska
  7. 2.1 27 km NNW of Glacier View, Alaska
  8. 2.3 28 km N of Chickaloon, Alaska
  9. 1.6 23 km SE of Chickaloon, Alaska
  10. 2.1 33 km SE of Chickaloon, Alaska
  11. 2.3 42 km NNW of Chickaloon, Alaska
  12. 1.6 39 km NNE of Chickaloon, Alaska
  13. 2.0 23 km NNW of Glacier View, Alaska
  14. 1.7 11 km E of Knik River, Alaska
  15. 1.8 20 km ESE 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.