Earthquake · automatic estimate, may change
M 2.5ml
103 km SE of Ugashik, Alaska
- When
- Magnitude
- M 2.5 (ml)
- Depth
- 5.0 km below the surface
- Felt
- no reports yet
- Status
- Automatic — a machine’s first estimate, which may change
USGS · last changed by USGS · we first saw it 3 hours ago
A magnitude 2.5 earthquake was recorded 103 km SE of Ugashik, Alaska at 05:29 UTC on 2026-10-03. This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.
How big was it?
This earthquake released about 170 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 89,000× the energy of this one
- Magna, Utah 2020 M 5.7 63,000× the energy of this one
- Around the size people start to feel M 3.0 5.6× the energy of this one
- This earthquake M 2.5 about 170 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 5.4 on 2022-04-28 — about 22,000 times the energy of this one.
Before 2016, the USGS record lists 10 earthquakes of M5 or more within 50 km; the five largest:
- 6.8 117 km SSE of Ugashik, Alaska · 18 km S of this epicentre
- 6.4 104 km SSE of Ugashik, Alaska · 23 km WSW of this epicentre
- 5.4 115 km SSE of Ugashik, Alaska · 13 km SSE of this epicentre
- 5.4 113 km SSE of Ugashik, Alaska · 16 km SSW of this epicentre
- 5.3 117 km SSE of Ugashik, Alaska · 21 km SSW 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 56.7590, -156.4070. Map © OpenStreetMap contributors.
Aftershocks so far
No further earthquakes have been recorded within 50 km since this one.
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
- 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.