4.0

M4.0 Earthquake 209 km SSE of Atka, AlaskaAugust 13, 2024

2024-08-13 17:37:52 UTC (2024-08-13) · approx. 5:37 AM UTC-12 local

MagnitudeM4.0(mb)
Time17:37 UTC5:37 AM UTC-12
Depth19.6 kmshallow crustal
Coordinates50.356°, -173.529°
Felt byNo felt reports
Status✓ Reviewed by USGS

On August 13, 2024 at 17:37 UTC, a magnitude 4.0 shallow crustal earthquake struck 209 km SSE of Atka, Alaska, at a depth of 19.6 km and coordinates 50.3564°, -173.5291°.

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.

Map showing earthquake epicenter at 50.36°, -173.53°

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 209 km SSE of Atka, Alaska

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

Earthquake Details

Magnitude
4.0 mb
Depth
19.6 km
shallow crustal
Location
50.3564°N
-173.5291°E
Intensity (MMI)
1.0
weak

Technical Information

Event ID
us6000njz2
Event Type
earthquake
Status
✓ Reviewed
Significance
246
Stations Used
40
Azimuthal Gap
186.0°
Min Station Distance
1.895°
RMS Residual
0.76 sec
Last Updated
2024-10-26 15:47:44 UTC

Common Questions

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

The magnitude 4.0 earthquake that struck 209 km SSE of Atka, Alaska on August 13, 2024 at 17:37 UTC had a depth of 19.6 km. For context, this was a light earthquake commonly felt near the epicenter.

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.

Understanding This Data

Magnitude 4.0 earthquakes are often felt but rarely cause damage.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: us6000njz2). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2024, August 13, 2024). M4.0 Earthquake 209 km SSE of Atka, AlaskaAugust 13, 2024. Retrieved October 26, 2024 from https://www.earthquaketracker.org/earthquakes/event/us6000njz2/