QuakeIndex

Earthquake · reviewed by a seismologist

M 5.5ml

92 km NNW of Aleneva, Alaska

· 88 km deep · released about 2.7 kilotons of TNT

10 km30 km60 km120 km N
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
Magnitude
M 5.5 (ml)
Depth
88 km below the surface
Felt
341 reports · strongest reported intensity V
Measured shaking
intensity IV (ShakeMap)
USGS impact alert
green
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 29 hours ago

A magnitude 5.5 earthquake was recorded 92 km NNW of Aleneva, Alaska at 18:34 UTC on 2026-10-06. 341 people have reported feeling it to USGS. This was a moderate earthquake. Shaking at this size can damage poorly built structures close to the epicentre.

At this magnitude and depth, people at rest would likely notice it out to about 246 km (153 mi) from the epicentre. 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 2.7 kilotons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 6.5 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 63× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 2.8× the energy of this one
  3. Magna, Utah 2020 M 5.7 2× the energy of this one
  4. This earthquake M 5.5 about 2.7 kilotons of TNT
  5. Around the size people start to feel M 3.0 this one released 5,600× 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 5.6 on 2017-08-31 — about 1.4 times the energy of this one.

Before 2016, the USGS record lists 7 earthquakes of M5 or more within 50 km; the five largest:

  1. 5.6 62 km SE of Kokhanok, Alaska · 37 km WNW of this epicentre
  2. 5.5 73 km WSW of Nanwalek, Alaska · 41 km ENE of this epicentre
  3. 5.5 73 km SSE of Kokhanok, Alaska · 33 km W of this epicentre
  4. 5.2 70 km SE of Kokhanok, Alaska · 28 km WNW of this epicentre
  5. 5.1 96 km SE of Pope-Vannoy Landing, Alaska · 18 km NE 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 58.8020, -153.6090. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 1.7 92 km SE of Kokhanok, Alaska
  2. 2.0 92 km NNW of Aleneva, Alaska
  3. 1.7 91 km SE of Kokhanok, Alaska
  4. 1.8 94 km SE of Kokhanok, Alaska
  5. 1.9 90 km SE of Kokhanok, 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.

Revisions

USGS refines a solution as more stations report. Every change we have seen is listed here.

What changedFromToWhen
felt reports340341
felt reports338340
felt reports337338
felt reports336337
felt reports335336
felt reports334335
felt reports332334
felt reports331332
felt reports329331
felt reports328329
felt reports326328
felt reports323326

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.