QuakeIndex

Earthquake · reviewed by a seismologist

M 4.6mw

Earthquake near Palmer, AK

No earthquake was likely felt in Palmer in the 24 hours to 11:37 pm AKST (08:37 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 4.6 earthquake was recorded 49 km (30 mi) east-northeast of Palmer, AK, at 2:36 am AKST on 27 January 2018 (11:36 UTC), 13 km deep.

USGS: 16 km SE of Chickaloon, Alaska

2:36 am AKST, Jan 27, 2018 · · 13 km deep · released about 120 tons of TNT

Every earthquake near Palmer Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Anchorage Municipality 82 kmMatanuska-Susitna Borough 91 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
2:36 am AKST on 27 January 2018 ()
Where
49 km (30 mi) east-northeast of Palmer, AK · earthquakes near Palmer
Magnitude
M 4.6 (mw)
Depth
13 km below the surface
Felt
no reports yet
Nearest
Anchorage Municipality, 82 km SW
Nearest mapped fault
Castle Mountain fault, 17 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 1190 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon.

At this magnitude and depth, people at rest would likely notice it out to about 148 km (92 mi) from the epicentre. In Palmer, 49 km away, the estimate is intensity III (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.

Likely felt in: Sutton-Alpine 36 km, intensity III · Lazy Mountain 40 km, intensity III · Butte 47 km, intensity III · Palmer 49 km, intensity III. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 120 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.6 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 1,400× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 63× the energy of this one
  3. Magna, Utah 2020 M 5.7 45× the energy of this one
  4. This earthquake M 4.6 about 120 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 250× more

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 (31 mi) since our catalogue begins in 2016. The previous largest was M 4.3 on 2018-01-26.

Before 2016, the USGS record lists 9 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.8 31 km SSW of Glacier View, Alaska · 30 km SE of this epicentre
  2. 6.4 23 km S of Glacier View, Alaska · 32 km ESE of this epicentre
  3. 6.4 37 km SSE of Glacier View, Alaska · 50 km ESE of this epicentre
  4. 5.9 15 km N of Glacier View, Alaska · 38 km NE of this epicentre
  5. 5.9 42 km S of Glacier View, Alaska · 46 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 61.7125, -148.2173. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Anchorage Municipality, AK 82 km (51 mi) SW earthquakes near Anchorage Municipality
Matanuska-Susitna Borough, AK 91 km (57 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

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

  1. 1.7 22 km N of Glacier View, Alaska
  2. 1.8 24 km SSE of Chickaloon, Alaska
  3. 1.5 23 km SSE of Chickaloon, Alaska
  4. 2.5 33 km SE of Chickaloon, Alaska
  5. 2.1 36 km SSW of Glacier View, Alaska
  6. 2.2 35 km SE of Chickaloon, Alaska
  7. 1.9 35 km SE of Chickaloon, Alaska
  8. 2.0 36 km SSE of Chickaloon, Alaska
  9. 2.9 7 km NNW of Chickaloon, Alaska
  10. 1.6 32 km NNW of Glacier View, Alaska
  11. 1.6 8 km SSW of Chickaloon, Alaska
  12. 2.0 39 km NNW of Glacier View, Alaska
  13. 1.8 23 km ESE of Chickaloon, Alaska
  14. 1.9 22 km WSW of Glacier View, Alaska
  15. 1.5 9 km NNW 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.