QuakeIndex

Earthquake · automatic estimate, may change

M 2.0ml

3 km NW of Petersville, Alaska

· 81 km deep · released about 30 lb of TNT

10 km30 km60 km120 km N Matanuska-Susitna Borough 73 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 2.0 (ml)
Depth
81 km below the surface
Felt
no reports yet
Nearest
Matanuska-Susitna Borough, 73 km ESE
Status
Automatic — a machine’s first estimate, which may change

USGS · last changed by USGS · we first saw it 3 days ago

A magnitude 2.0 earthquake was recorded 3 km NW of Petersville, Alaska at 14:36 UTC on 2026-09-29. This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 30 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.0 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 500,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 350,000× the energy of this one
  3. Around the size people start to feel M 3.0 32× the energy of this one
  4. This earthquake M 2.0 about 30 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 4.6 on 2025-08-06 — about 7,900 times the energy of this one.

Before 2016, the USGS record lists 8 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.3 Central Alaska · 31 km W of this epicentre
  2. 5.4 48 km N of Petersville, Alaska · 47 km N of this epicentre
  3. 5.4 32 km W of Petersville, Alaska · 30 km W of this epicentre
  4. 5.4 33 km N of Skwentna, Alaska · 38 km SW of this epicentre
  5. 5.1 31 km W of Petersville, Alaska · 29 km W 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 62.5130, -150.8140. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Matanuska-Susitna Borough, AK 73 km (45 mi) ESE earthquakes near Matanuska-Susitna Borough

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

Aftershocks so far

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

  1. 1.7 30 km WNW of Petersville, Alaska
  2. 2.1 37 km N of Petersville, Alaska
  3. 2.2 33 km WNW of Petersville, 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
location3 km WNW of Petersville, Alaska3 km NW of Petersville, Alaska
longitude-150.82-150.81
latitude62.5162.51
depth80.480.7
magnitude1.92

On USGS

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