42 km WSW of Nanwalek, Alaska

A magnitude 1.9 earthquake was recorded 42 km WSW of Nanwalek, Alaska at 09:37 UTC on 2026-09-30. This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 21 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

1. Mineral, Virginia 2011 M 5.8 710,000× the energy of this one
2. Magna, Utah 2020 M 5.7 500,000× the energy of this one
3. Around the size people start to feel M 3.0 45× the energy of this one
4. This earthquake M 1.9 about 21 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 5.8 on 2019-05-27 — about 710,000 times the energy of this one.

Before 2016, the USGS record lists 13 earthquakes of M5 or more within 50 km; the five largest:

1. 6.4 25 km NW of Nanwalek, Alaska · 38 km NNE of this epicentre Jun 24, 1963
2. 6.0 61 km WSW of Nanwalek, Alaska · 19 km WSW of this epicentre Dec 5, 1942
3. 5.9 Southern Alaska · 30 km NNW of this epicentre Jan 24, 2009
4. 5.8 63 km WSW of Nanwalek, Alaska · 22 km SW of this epicentre May 19, 2000
5. 5.6 67 km SE of Pedro Bay, Alaska · 39 km NW of this epicentre Feb 12, 1995

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 59.2050, -152.6050. Map © OpenStreetMap contributors.

Aftershocks so far

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

1. 1.9 54 km WNW of Nanwalek, Alaska 02:52 UTC
2. 1.9 33 km WSW of Nanwalek, Alaska 18:30 UTC
3. 3.4 23 km NW of Nanwalek, Alaska 03:29 UTC
4. 1.5 34 km WSW of Anchor Point, Alaska 00:29 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 01:40 UTC. 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.

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.