158 km ESE of Chignik, Alaska

Yes. A magnitude 4.4 earthquake was recorded 158 km ESE of Chignik, Alaska at 10:23 UTC on 2017-12-04, 56 km deep.

2017-12-04 10:23 UTC · 56 km deep · released about 60 tons of TNT

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: 2017-12-04 10:23 UTC
Magnitude: M 4.4 (ml)
Depth: 56 km below the surface
Felt: no reports yet
Measured shaking: intensity III (ShakeMap)
USGS impact alert: green
Status: Reviewed by a seismologist

USGS · last changed by USGS 1191 days ago · we first saw it 1191 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon.

At this magnitude and depth, people at rest would likely notice it out to about 117 km (73 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 60 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.4 would have released about 32 times as much.

Northridge, California 1994 M 6.7 2,800× the energy of this one
Mineral, Virginia 2011 M 5.8 130× the energy of this one
Magna, Utah 2020 M 5.7 89× the energy of this one
This earthquake M 4.4 about 60 tons of TNT
Around the size people start to feel M 3.0 this one released 130× 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 (31 mi) since our catalogue begins in 2016. No other earthquake of M4 or more has been recorded this close in that time.

Before 2016, the USGS record lists 10 earthquakes of M5 or more within 50 km; the five largest:

7.0 113 km ESE of Chignik, Alaska · 48 km W of this epicentre May 4, 1923
6.9 143 km ESE of Chignik, Alaska · 18 km W of this epicentre Feb 13, 1951
6.9 171 km SW of Akhiok, Alaska · 15 km SE of this epicentre Feb 6, 1964
6.1 132 km E of Chignik, Alaska · 44 km NNW of this epicentre Sep 13, 1911
6.1 118 km ESE of Chignik, Alaska · 40 km WNW of this epicentre Mar 16, 1940

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

Map loads when it scrolls into view

Aftershocks so far

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

2.4 137 km E of Chignik, Alaska 16:55 UTC
2.7 132 km SW of Akhiok, Alaska 16:27 UTC
2.1 south of Alaska 22:25 UTC
2.5 130 km SW of Akhiok, Alaska 02:11 UTC
3.4 119 km ESE of Chignik, Alaska 18:04 UTC
3.0 153 km ESE of Chignik, Alaska 12:21 UTC
2.9 126 km SW of Akhiok, AK 07:57 UTC
2.4 130 km SW of Akhiok, Alaska 05:35 UTC
2.8 142 km E of Chignik, Alaska 03:06 UTC
2.5 172 km ESE of Chignik, Alaska 17:49 UTC
3.0 136 km E of Chignik, Alaska 01:35 UTC
2.0 139 km E of Chignik, Alaska 05:20 UTC
2.6 134 km ESE of Chignik, Alaska 09:04 UTC
2.0 131 km E of Chignik, Alaska 05:13 UTC
3.6 155 km SW of Akhiok, Alaska 03:09 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 10:39 UTC. 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.