Earthquake · reviewed by a seismologist
M 1.7ml
75 km WSW of Cantwell, Alaska
Yes. A magnitude 1.7 earthquake was recorded 75 km WSW of Cantwell, Alaska, at 4:40 am AKST on 29 November 2021 (13:40 UTC), 105 km deep.
- When
- Magnitude
- M 1.7 (ml)
- Depth
- 105 km below the surface
- Felt
- no reports yet
- Nearest
- Denali Borough, 59 km NNE
- Nearest mapped fault
- Denali fault, 10 km from its surface trace — near is not the same as on
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 1775 days ago
This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.
At this magnitude and depth it was probably too small to be felt, even directly above it. 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 11 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 1,400,000× the energy of this one
- Magna, Utah 2020 M 5.7 1,000,000× the energy of this one
- Around the size people start to feel M 3.0 89× the energy of this one
- This earthquake M 1.7 about 11 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 5.0 on 2018-07-10 — about 89,000 times the energy of this one.
Before 2016, the USGS record lists 19 earthquakes of M5 or more within 50 km; the five largest:
- 7.2 Mount McKinley (Denali) area, Alaska · 18 km N of this epicentre
- 6.4 Mount McKinley (Denali) area, Alaska · 30 km NNW of this epicentre
- 5.7 66 km ESE of Denali National Park, Alaska · 12 km WNW of this epicentre
- 5.5 53 km ESE of Denali National Park, Alaska · 30 km NNW of this epicentre
- 5.5 59 km SE of Denali National Park, Alaska · 30 km W 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 63.1759, -150.3759. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Denali Borough, AK | 59 km (37 mi) | NNE | earthquakes near Denali Borough |
| Matanuska-Susitna Borough, AK | 111 km (69 mi) | SSE | earthquakes near Matanuska-Susitna Borough |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
58 earthquakes have been recorded within 50 km since this one.
- 1.9 71 km SE of Denali National Park, Alaska
- 1.6 45 km W of Cantwell, Alaska
- 1.6 63 km WSW of Cantwell, Alaska
- 1.8 61 km WSW of Cantwell, Alaska
- 1.7 55 km WSW of Cantwell, Alaska
- 2.0 60 km NNE of Petersville, Alaska
- 2.0 71 km SE of Denali National Park, Alaska
- 2.3 65 km SE of Denali National Park, Alaska
- 1.5 70 km ESE of Denali National Park, Alaska
- 1.5 61 km ESE of Denali National Park, Alaska
- 1.8 55 km WNW of Cantwell, Alaska
- 1.7 Central Alaska
- 2.2 62 km SE of Denali National Park, Alaska
- 2.2 71 km SE of Denali National Park, Alaska
- 1.7 37 km NNE of Petersville, 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.