QuakeIndex

Earthquake · automatic estimate, may change

M 1.8ml

51 km W of Happy Valley, Alaska

· 99 km deep · released about 15 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Kenai Peninsula Borough 45 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
Magnitude
M 1.8 (ml)
Depth
99 km below the surface
Felt
no reports yet
Nearest
Kenai Peninsula Borough, 45 km NNE
Status
Automatic — a machine’s first estimate, which may change

USGS · last changed by USGS · we first saw it 2 days ago

A magnitude 1.8 earthquake was recorded 51 km W of Happy Valley, Alaska at 08:25 UTC on 2026-10-01. This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 15 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 710,000× the energy of this one
  3. Around the size people start to feel M 3.0 63× the energy of this one
  4. This earthquake M 1.8 about 15 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 5.6 on 2017-03-02 — about 500,000 times the energy of this one.

Before 2016, the USGS record lists 24 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.4 75 km WNW of Ninilchik, Alaska · 36 km NNW of this epicentre
  2. 6.4 52 km ENE of Pedro Bay, Alaska · 33 km WSW of this epicentre
  3. 6.2 16 km WNW of Happy Valley, Alaska · 36 km E of this epicentre
  4. 6.2 70 km E of Port Alsworth, Alaska · 28 km NW of this epicentre
  5. 6.1 73 km WNW of Ninilchik, Alaska · 43 km NNW 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 59.9980, -152.6500. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Kenai Peninsula Borough, AK 45 km (28 mi) NNE earthquakes near Kenai Peninsula Borough

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

Aftershocks so far

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

  1. 0.3 63 km ENE of Pedro Bay, Alaska
  2. -1.0 65 km ENE of Pedro Bay, Alaska
  3. -1.1 64 km ENE of Pedro Bay, Alaska
  4. -1.2 64 km ENE of Pedro Bay, Alaska
  5. -0.8 64 km ENE of Pedro Bay, Alaska
  6. -0.4 63 km ENE of Pedro Bay, Alaska
  7. -1.2 64 km ENE of Pedro Bay, Alaska
  8. 1.7 62 km WNW of Ninilchik, Alaska
  9. -0.7 63 km ENE of Pedro Bay, Alaska
  10. -0.9 64 km ENE of Pedro Bay, Alaska
  11. 1.9 65 km ENE of Pedro Bay, Alaska
  12. 1.0 62 km ENE of Pedro Bay, Alaska
  13. 0.4 60 km E of Pedro Bay, Alaska
  14. 2.1 55 km WNW of Happy Valley, Alaska
  15. -0.7 65 km ENE of Pedro Bay, 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
location54 km WNW of Anchor Point, Alaska51 km W of Happy Valley, Alaska
longitude-152.71-152.65
latitude59.9960
depth98.198.8
magnitude0.81.8

On USGS

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