Earthquake · reviewed by a seismologist
M 2.1ml
Earthquake near Girdwood, AK
No earthquake was likely felt in Girdwood in the 24 hours to 2:29 am AKST (11:29 UTC). The last one was M 1.8, 8 km (5 mi) SE, at 10:01 am AKDT on 19 October 2026, estimated intensity II (weak) in town. Every earthquake near Girdwood
This page: a magnitude 2.1 earthquake was recorded 47 km (29 mi) south-southwest of Girdwood, AK, at 4:18 am AKST on 23 February 2020 (13:18 UTC), 26 km deep.
USGS: 12 km NW of Moose Pass, Alaska
75 km (47 mi) SSE of Anchorage, AK
- When
- 4:18 am AKST on 23 February 2020 ()
- Where
- 47 km (29 mi) south-southwest of Girdwood, AK · earthquakes near Girdwood
- Magnitude
- M 2.1 (ml)
- Depth
- 26 km below the surface
- Felt
- no reports yet
- Nearest
- Anchorage Municipality, 69 km N
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2434 days ago
Earthquake alerts for Girdwood, AK
Get a notification in this browser when USGS records an earthquake near Girdwood, AK. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
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. In Girdwood, 47 km away, the estimate is intensity II (weak). 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 43 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 350,000× the energy of this one
- Magna, Utah 2020 M 5.7 250,000× the energy of this one
- Around the size people start to feel M 3.0 22× the energy of this one
- This earthquake M 2.1 about 43 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 4.2 on 2016-02-15 — about 1,400 times the energy of this one.
Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:
- 6.8 24 km ENE of Sterling, Alaska · 48 km WNW of this epicentre
- 6.6 3 km SW of Bear Creek, Alaska · 47 km S of this epicentre
- 5.7 13 km S of Girdwood, Alaska · 34 km NNE of this epicentre
- 5.6 17 km W of Whittier, Alaska · 36 km NE of this epicentre
- 5.3 16 km WSW of Whittier, Alaska · 35 km ENE 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 60.5642, -149.5315. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Anchorage Municipality, AK | 69 km (43 mi) | N | earthquakes near Anchorage Municipality |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
56 earthquakes have been recorded within 50 km since this one.
- 1.7 5 km WSW of Hope, Alaska
- 1.7 1 km SE of Girdwood, Alaska
- 1.7 21 km SSW of Cooper Landing, Alaska
- 1.7 9 km SSW of Cooper Landing, Alaska
- 2.0 3 km WSW of Hope, Alaska
- 1.7 21 km SSW of Hope, Alaska
- 1.6 9 km NW of Moose Pass, Alaska
- 2.0 15 km NW of Cooper Landing, Alaska
- 1.7 13 km NW of Bear Creek, Alaska
- 1.7 25 km SW of Hope, Alaska
- 1.9 15 km NW of Moose Pass, Alaska
- 1.7 6 km W of Hope, Alaska
- 3.5 10 km NE of Cooper Landing, Alaska
- 1.8 15 km WSW of Hope, Alaska
- 2.5 13 km NNW of Cooper Landing, 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.