4.0

M4.0 Earthquake 19 km WSW of Salcha, AlaskaNovember 17, 2022

2022-11-17 22:34:41 UTC (2022-11-17) · approx. 12:34 PM UTC-10 local

Felt by 277 people across surrounding communities.

MagnitudeM4.0(mwr)
Time22:34 UTC12:34 PM UTC-10
Depth14.6 kmshallow crustal
Coordinates64.481°, -147.293°
Felt by277DYFI responses· max MMI 3.6
Status✓ Reviewed by USGS

On November 17, 2022 at 22:34 UTC, a magnitude 4.0 shallow crustal earthquake struck 19 km WSW of Salcha, Alaska, at a depth of 14.6 km and coordinates 64.4814°, -147.2927°. The earthquake was reported felt by 277 peopleacross surrounding communities, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 3.6 (light).

Physical scale: An earthquake of magnitude 4.0 releases seismic energy equivalent to roughly 15 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 347 m — 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 64.48°, -147.29°

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 M4.0 earthquake near 19 km WSW of Salcha, Alaska

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

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 277 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 M4.0 earthquake near 19 km WSW of Salcha, Alaska

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

Earthquake Details

Magnitude
4.0 mwr
Depth
14.6 km
shallow crustal
Location
64.4814°N
-147.2927°E
Felt Reports
277
DYFI responses
Intensity (MMI)
3.6
light
Community Intensity
4.1
CDI from reports

Technical Information

Event ID
ak022er8tbc2
Event Type
earthquake
Status
✓ Reviewed
Significance
360
RMS Residual
0.89 sec
Last Updated
2023-01-28 19:58:24 UTC

Common Questions

How strong was the magnitude 4.0 earthquake near Salcha, Alaska?

The magnitude 4.0 earthquake that struck 19 km WSW of Salcha, Alaska on November 17, 2022 at 22:34 UTC had a depth of 14.6 km. It was felt by 277 people with maximum shaking intensity of MMI 3.6 (light). For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at 64.4814°, -147.2927°, which is 19 km WSW of Salcha, Alaska. View all earthquakes in Alaska.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.0 earthquakes can continue for several days 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 4.0 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: ak022er8tbc2). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2022, November 17, 2022). M4.0 Earthquake 19 km WSW of Salcha, AlaskaNovember 17, 2022. Retrieved January 28, 2023 from https://www.earthquaketracker.org/earthquakes/event/ak022er8tbc2/