M5.7 Earthquake south of Alaska — December 1, 2020
2020-12-01 16:35:48 UTC (2020-12-01) · approx. 6:35 AM UTC-10 local
Felt by 1 person across nearby locations. 0
On December 1, 2020 at 16:35 UTC, a magnitude 5.7 shallow crustal earthquake struck south of Alaska, at a depth of 10.0 km and coordinates 53.6855°, -150.5827°.0 The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected.
Physical scale: An earthquake of magnitude 5.7 releases seismic energy equivalent to roughly 5 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 5.2 km — a useful intuition for the size of the slip patch on the fault.
The epicenter is located in Alaska, a region characterized by Pacific Plate subduction beneath the North American Plate, producing frequent megathrust and crustal earthquakes along the Aleutian arc. The nearest mapped fault system is the Aleutian megathrust. View all earthquakes in Alaska.
Learn more: Magnitude scale · Aftershock sequences

ShakeMap — predicted shaking intensity
Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.

Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS
Did You Feel It? — community-reported shaking
Aggregated felt-report intensity from 1 citizen response to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.

Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report
Earthquake Details
-150.5827°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 5.7 earthquake south of Alaska?
The magnitude 5.7 earthquake that struck south of Alaska on December 1, 2020 at 16:35 UTC had a depth of 10.0 km. For context, this was a moderate earthquake that could be widely felt.
Where did the earthquake occur?
The earthquake epicenter was located at 53.6855°, -150.5827°, which is south of Alaska. View all earthquakes in Alaska.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.7 earthquakes can continue for days to weeks and gradually diminish over time.
Has Alaska had earthquakes this big before?
The largest recorded earthquake in Alaska was the M9.2 Great Alaska earthquake of March 27, 1964. Today's magnitude 5.7 event is significantly smaller than that historical record.
Authoritative source: USGS event page (event ID: us7000clp0). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2020, December 1, 2020). M5.7 Earthquake south of Alaska — December 1, 2020. Retrieved December 22, 2025 from https://www.earthquaketracker.org/earthquakes/event/us7000clp0/