Earthquake · automatic estimate, may change
M 2.8ml
107 km SE of Chignik, Alaska
Yes. A magnitude 2.8 earthquake was recorded 107 km SE of Chignik, Alaska at 01:20 UTC on 2021-06-09, 4.9 km deep. The magnitude and location are an automatic first estimate and may change.
- When
- Magnitude
- M 2.8 (ml)
- Depth
- 4.9 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 1906 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 27 km (17 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 480 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 32,000× the energy of this one
- Magna, Utah 2020 M 5.7 22,000× the energy of this one
- Around the size people start to feel M 3.0 2× the energy of this one
- This earthquake M 2.8 about 480 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
No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.
Before 2016, the USGS record lists 12 earthquakes of M5 or more within 50 km; the five largest:
- 7.0 113 km ESE of Chignik, Alaska · 22 km NE of this epicentre
- 6.9 143 km ESE of Chignik, Alaska · 48 km ENE of this epicentre
- 6.7 121 km SE of Chignik, Alaska · 29 km SSW of this epicentre
- 6.6 128 km SE of Chignik, Alaska · 21 km ESE of this epicentre
- 6.4 77 km ESE of Chignik, Alaska · 49 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 55.7038, -157.0351. Map © OpenStreetMap contributors.
Aftershocks so far
53 earthquakes have been recorded within 50 km since this one.
- 2.7 132 km SE of Chignik, Alaska
- 2.8 138 km SE of Chignik, Alaska
- 2.7 146 km SE of Chignik, Alaska
- 4.0 139 km SE of Chignik, Alaska
- 2.4 136 km SE of Chignik, Alaska
- 2.5 125 km SE of Chignik, Alaska
- 3.0 152 km SE of Chignik, Alaska
- 2.6 151 km SE of Chignik, Alaska
- 3.6 150 km SE of Chignik, Alaska
- 2.6 133 km SE of Chignik, Alaska
- 2.9 129 km SE of Chignik, Alaska
- 2.8 141 km SE of Chignik, Alaska
- 2.3 104 km ESE of Chignik, Alaska
- 2.1 71 km SE of Chignik, Alaska
- 2.5 128 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.