Earthquake · reviewed by a seismologist
M 5.5ml
92 km NNW of Aleneva, Alaska
- 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.
- Northridge, California 1994 M 6.7 63× the energy of this one
- Mineral, Virginia 2011 M 5.8 2.8× the energy of this one
- Magna, Utah 2020 M 5.7 2× the energy of this one
- This earthquake M 5.5 about 2.7 kilotons of TNT
- 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:
- 5.6 62 km SE of Kokhanok, Alaska · 37 km WNW of this epicentre
- 5.5 73 km WSW of Nanwalek, Alaska · 41 km ENE of this epicentre
- 5.5 73 km SSE of Kokhanok, Alaska · 33 km W of this epicentre
- 5.2 70 km SE of Kokhanok, Alaska · 28 km WNW of this epicentre
- 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.
- 1.7 92 km SE of Kokhanok, Alaska
- 2.0 92 km NNW of Aleneva, Alaska
- 1.7 91 km SE of Kokhanok, Alaska
- 1.8 94 km SE of Kokhanok, Alaska
- 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 changed | From | To | When |
|---|---|---|---|
| felt reports | 340 | 341 | |
| felt reports | 338 | 340 | |
| felt reports | 337 | 338 | |
| felt reports | 336 | 337 | |
| felt reports | 335 | 336 | |
| felt reports | 334 | 335 | |
| felt reports | 332 | 334 | |
| felt reports | 331 | 332 | |
| felt reports | 329 | 331 | |
| felt reports | 328 | 329 | |
| felt reports | 326 | 328 | |
| felt reports | 323 | 326 |
On USGS
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.