5.1

M5.1 Earthquake 54 km NNE of Petersville, AlaskaDecember 1, 2023

2023-12-01 05:50:26 UTC (2023-12-01) · approx. 7:50 PM UTC-10 local

Felt by 679 people across surrounding communities.

MagnitudeM5.1(mww)
Time05:50 UTC7:50 PM UTC-10
Depth101.7 kmintermediate depth
Coordinates62.957°, -150.435°
Felt by679DYFI responses· max MMI 3.5
Status✓ Reviewed by USGS· Tsunami evaluation· green PAGER
green Alertno significant casualties or damage expected
Tsunami Warning Issued

On December 1, 2023 at 05:50 UTC, a magnitude 5.1 intermediate depth earthquake struck 54 km NNE of Petersville, Alaska, at a depth of 101.7 km and coordinates 62.9574°, -150.4351°. The earthquake was reported felt by 679 peopleacross surrounding communities, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 3.5 (light). The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected. The nearest populated place is Y (population 1,260).

Physical scale: An earthquake of magnitude 5.1 releases seismic energy equivalent to roughly 674 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 2.0 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

Nearest Populated Places

Ypop. 1,260
MMI 3.4 (light)
Willowpop. 2,102
MMI 3.2 (light)
Healypop. 1,021
MMI 3.2 (light)
Meadow Lakespop. 7,570
MMI 3.1 (light)
Tanainapop. 8,197
MMI 3.1 (light)
Houstonpop. 1,912
MMI 3.1 (light)
Map showing earthquake epicenter at 62.96°, -150.44°

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.

USGS ShakeMap intensity contours for the M5.1 earthquake near 54 km NNE of Petersville, Alaska

Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 679 citizen responses to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.

USGS DYFI community-reported intensity map for the M5.1 earthquake near 54 km NNE of Petersville, Alaska

Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report

Population exposure (USGS PAGER)

Estimated population that experienced each level of shaking. Based on the USGS PAGER rapid impact assessment, which combines ShakeMap output with global population grids.

Shaking intensity (MMI)DescriptionPopulation exposed
MMI 3weak212,414
MMI 4light1,706

Earthquake Details

Magnitude
5.1 mww
Depth
101.7 km
intermediate depth
Location
62.9574°N
-150.4351°E
Felt Reports
679
DYFI responses
Intensity (MMI)
3.5
light
Community Intensity
5.4
CDI from reports

Technical Information

Event ID
ak023fe4b796
Event Type
earthquake
Status
✓ Reviewed
Significance
767
RMS Residual
0.71 sec
Last Updated
2025-11-15 20:54:36 UTC

Common Questions

How strong was the magnitude 5.1 earthquake near Petersville, Alaska?

The magnitude 5.1 earthquake that struck 54 km NNE of Petersville, Alaska on December 1, 2023 at 05:50 UTC had a depth of 101.7 km. It was felt by 679 people with maximum shaking intensity of MMI 3.5 (light). For context, this was a moderate earthquake that could be widely felt.

Where did the earthquake occur?

The earthquake epicenter was located at 62.9574°, -150.4351°, which is 54 km NNE of Petersville, Alaska. The nearest populated place is Y (population 1,260). View all earthquakes in Alaska.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.1 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 5.1 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: ak023fe4b796). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, December 1, 2023). M5.1 Earthquake 54 km NNE of Petersville, AlaskaDecember 1, 2023. Retrieved November 15, 2025 from https://www.earthquaketracker.org/earthquakes/event/ak023fe4b796/