QuakeIndex

Earthquake · reviewed by a seismologist

M 3.9ml

Earthquake near Fishhook, AK

No earthquake was likely felt in Fishhook in the 24 hours to 6:07 am AKST (15:07 UTC). The last one was M 4.4, 118 km (73 mi) E, at 11:11 am AKDT on 30 October 2026, estimated intensity II (weak) in town; 54 felt reports to USGS. Every earthquake near Fishhook

This page: a magnitude 3.9 earthquake was recorded 23 km (14 mi) north of Fishhook, AK, at 4:08 pm AKDT on 3 October 2023 (00:08 UTC), 43 km deep. 173 people have reported feeling it to USGS.

USGS: 23 km N of Fishhook, Alaska

87 km (54 mi) NNE of Anchorage, AK

4:08 pm AKDT, Oct 3, 2023 · · 43 km deep · released about 11 tons of TNT

Every earthquake near Fishhook Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Matanuska-Susitna Borough 37 kmAnchorage Municipality 86 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
4:08 pm AKDT on 3 October 2023 ()
Where
23 km (14 mi) north of Fishhook, AK · earthquakes near Fishhook
Magnitude
M 3.9 (ml)
Depth
43 km below the surface
Felt
173 reports · strongest reported intensity III
Measured shaking
intensity III (ShakeMap)
USGS impact alert
green
Nearest
Matanuska-Susitna Borough, 37 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 765 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 78 km (48 mi) from the epicentre. In Fishhook, 23 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.

Likely felt in: Fishhook 23 km, intensity II · Sutton-Alpine 34 km, intensity II · Tanaina 36 km, intensity II · Susitna North 37 km, intensity II · Palmer 40 km, intensity II · Lazy Mountain 40 km, intensity II · Willow 45 km, intensity II · Butte 47 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 11 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.9 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 16,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 710× the energy of this one
  3. Magna, Utah 2020 M 5.7 500× the energy of this one
  4. This earthquake M 3.9 about 11 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 22× 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 since 2016 was M 4.5 on 2023-01-16 — about 7.9 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. 5.9 23 km NE of Willow, Alaska · 23 km W of this epicentre
  2. 5.8 37 km ENE of Susitna North, Alaska · 39 km N of this epicentre
  3. 5.8 14 km NNE of Fishhook, Alaska · 15 km SE of this epicentre
  4. 5.4 25 km NNW of Willow, Alaska · 44 km W of this epicentre
  5. 5.3 3 km NNE of Houston, Alaska · 41 km SW 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 61.9486, -149.3030. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Matanuska-Susitna Borough, AK 37 km (23 mi) NNW earthquakes near Matanuska-Susitna Borough
Anchorage Municipality, AK 86 km (54 mi) S earthquakes near Anchorage Municipality

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. 1.5 18 km E of Susitna North, Alaska
  2. 2.1 27 km ENE of Susitna North, Alaska
  3. 1.9 9 km NNW of Houston, Alaska
  4. 1.5 12 km NE of Susitna North, Alaska
  5. 1.7 12 km NNE of Houston, Alaska
  6. 1.7 5 km SW of Fishhook, Alaska
  7. 1.6 21 km WNW of Fishhook, Alaska
  8. 1.6 18 km ENE of Willow, Alaska
  9. 1.5 14 km NNE of Houston, Alaska
  10. 2.0 25 km NNW of Fishhook, Alaska
  11. 1.6 4 km SSW of Houston, Alaska
  12. 2.8 Central Alaska
  13. 2.9 10 km ENE of Susitna North, Alaska
  14. 2.5 26 km ENE of Susitna North, Alaska
  15. 2.0 14 km NNW of Meadow 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.