Earthquake · reviewed by a seismologist
M 3.1ml
198 km SE of Chignik, Alaska
Yes. A magnitude 3.1 earthquake was recorded 198 km SE of Chignik, Alaska at 14:35 UTC on 2022-06-30, 3.9 km deep.
- When
- Magnitude
- M 3.1 (ml)
- Depth
- 3.9 km below the surface
- Felt
- no reports yet
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 1531 days ago
This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.
At this magnitude and depth, people at rest would likely notice it out to about 42 km (26 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 1,300 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.
- Northridge, California 1994 M 6.7 250,000× the energy of this one
- Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
- Magna, Utah 2020 M 5.7 7,900× the energy of this one
- This earthquake M 3.1 about 1,300 lb of TNT
- Around the size people start to feel M 3.0 this one released 1.4× 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 since 2016 was M 5.6 on 2021-09-16 — about 5,600 times the energy of this one.
Before 2016, the USGS record lists 10 earthquakes of M5 or more within 50 km; the five largest:
- 7.0 164 km SE of Chignik, Alaska · 39 km NNW of this epicentre
- 6.2 189 km SE of Chignik, Alaska · 18 km WSW of this epicentre
- 6.1 210 km SE of Chignik, Alaska · 41 km ENE of this epicentre
- 6.0 223 km SSW of Akhiok, Alaska · 47 km ENE of this epicentre
- 6.0 168 km SE of Chignik, Alaska · 32 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 54.9888, -156.2617. Map © OpenStreetMap contributors.
Aftershocks so far
54 earthquakes have been recorded within 50 km since this one.
- 3.3 198 km SE of Perryville, Alaska
- 3.3 203 km SE of Perryville, Alaska
- 3.7 199 km SE of Chignik, Alaska
- 2.8 171 km SE of Chignik, Alaska
- 2.8 213 km SE of Perryville, Alaska
- 2.7 195 km SE of Chignik, Alaska
- 3.7 207 km SE of Chignik, Alaska
- 2.4 195 km SE of Chignik, Alaska
- 2.7 193 km SE of Chignik, Alaska
- 3.7 201 km SE of Chignik, Alaska
- 3.4 194 km SE of Chignik, Alaska
- 2.8 209 km SE of Chignik, Alaska
- 4.7 south of Alaska
- 2.6 165 km SE of Chignik, Alaska
- 3.0 170 km SE of Chignik, 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.
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.