6.3

M6.3 Earthquake near Rat Islands, Aleutian Islands, AlaskaDecember 14, 2022

2022-12-14 18:40:26 UTC (2022-12-14) · approx. 6:40 AM UTC+12 local

Felt by 2 people across nearby locations. Maximum shaking intensity MMI 5.7 (strong).

MagnitudeM6.3(mww)
Time18:40 UTC6:40 AM UTC+12
Depth73.0 kmintermediate depth
Coordinates51.608°, 178.597°
Felt by2DYFI responses· max MMI 5.7
Status✓ Reviewed by USGS· Tsunami evaluation· green PAGER
green Alertno significant casualties or damage expected
Tsunami Warning Issued

On December 14, 2022 at 18:40 UTC, a magnitude 6.3 intermediate depth earthquake struck near Rat Islands, Aleutian Islands, Alaska, at a depth of 73.0 km and coordinates 51.6079°, 178.5971°. The earthquake was reported felt by 2 peopleacross nearby locations, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 5.7 (strong). The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected. This earthquake was detected by 248 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 611, making it a moderate-impact event.

Physical scale: An earthquake of magnitude 6.3 releases seismic energy equivalent to roughly 43 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 13 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

Map showing earthquake epicenter at 51.61°, 178.60°

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 M6.3 earthquake near Rat Islands, Aleutian Islands, Alaska

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

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 2 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 M6.3 earthquake near Rat Islands, Aleutian Islands, Alaska

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

Earthquake Details

Magnitude
6.3 mww
Depth
73.0 km
intermediate depth
Location
51.6079°N
178.5971°E
Felt Reports
2
DYFI responses
Intensity (MMI)
5.7
strong
Community Intensity
0.0
CDI from reports

Technical Information

Event ID
us6000j985
Event Type
earthquake
Status
✓ Reviewed
Significance
611
Stations Used
248
Azimuthal Gap
31.0°
Min Station Distance
0.345°
RMS Residual
1.20 sec
Last Updated
2024-11-29 00:31:36 UTC

Common Questions

How strong was the magnitude 6.3 earthquake near Rat Islands, Aleutian Islands, Alaska?

The magnitude 6.3 earthquake that struck near Rat Islands, Aleutian Islands, Alaska on December 14, 2022 at 18:40 UTC had a depth of 73.0 km. It was felt by 2 people with maximum shaking intensity of MMI 5.7 (strong). For context, this was a strong earthquake capable of causing significant damage.

Where did the earthquake occur?

The earthquake epicenter was located at 51.6079°, 178.5971°, which is near Rat Islands, Aleutian Islands, Alaska. View all earthquakes in Alaska.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 6.3 earthquakes can continue for weeks to months 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 6.3 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us6000j985). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2022, December 14, 2022). M6.3 Earthquake near Rat Islands, Aleutian Islands, AlaskaDecember 14, 2022. Retrieved November 29, 2024 from https://www.earthquaketracker.org/earthquakes/event/us6000j985/