M4.3 Earthquake 84 km WSW of Atka, Alaska — December 12, 2023
2023-12-12 20:32:01 UTC (2023-12-12) · approx. 8:32 AM UTC-12 local
On December 12, 2023 at 20:32 UTC, a magnitude 4.3 shallow crustal earthquake struck 84 km WSW of Atka, Alaska, at a depth of 47.8 km and coordinates 51.8035°, -175.2579°.
Physical scale: An earthquake of magnitude 4.3 releases seismic energy equivalent to roughly 43 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 558 m — a useful intuition for the size of the slip patch on the fault.
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
Earthquake Details
-175.2579°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 4.3 earthquake near Atka, Alaska?
The magnitude 4.3 earthquake that struck 84 km WSW of Atka, Alaska on December 12, 2023 at 20:32 UTC had a depth of 47.8 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 4.3 earthquakes can continue for several days and gradually diminish over time.
Actions
Understanding This Data
Magnitude 4.3 earthquakes are often felt but rarely cause damage.
Authoritative source: USGS event page (event ID: us7000lihh). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2023, December 12, 2023). M4.3 Earthquake 84 km WSW of Atka, Alaska — December 12, 2023. Retrieved February 17, 2024 from https://www.earthquaketracker.org/earthquakes/event/us7000lihh/