On October 4, 2024, a magnitude 1.6 earthquake occurred approximately 37 miles east of Chenega Bay, Alaska, at a depth of 12.1 miles. This event has not yet been analyzed by a seismologist and occurred in a region known for its significant seismic activity due to tectonic interactions among various plates.
On October 4, 2024, at 05:14:30 AKDT (13:14:30 UTC), a minor earthquake with a magnitude of 1.6 was recorded approximately 37 miles east of Chenega Bay, Alaska. This seismic event occurred at a depth of about 12.1 miles (19 kilometers) and had not yet been reviewed by a seismologist. The epicenter was notably situated 46 miles south of Tatitlek, 47 miles southwest of Cordova, and various other notable distances from landmarks including 66 miles south of Valdez and 90 miles southeast of Girdwood. The area has a rich seismic history characterized by significant tectonic activity due to the interaction of various geological features in Southcentral Alaska.
The tectonic dynamics of Southern Alaska are quite complex, resulting predominantly from the interactions among the Pacific and North American tectonic plates. The megathrust fault, which delineates the contact zone between the subducting Pacific Plate and the overriding North American Plate, has been responsible for some of the most powerful seismic events in history, such as the 1964 M9.2 Great Alaska Earthquake, one of the largest earthquakes recorded globally. In addition, the Wadati-Benioff Zone, where intermediate-depth seismicity (below 20 miles) occurs, is a crucial area as it marks the descent of the Pacific Plate towards the Earth’s mantle. Other sources of crustal seismicity are linked to the faults and folds in the Cook Inlet basin, particularly the Castle Mountain Fault and various geological structures that can generate strong earthquakes. Historical events, including the significant 1933 M6.9 earthquake and the more recent 2016 and 2018 quakes, illustrate the ongoing seismic risk in the region.
In summary, the minor earthquake recorded near Chenega Bay on October 4, 2024, is a reminder of the tectonic complexities in Southern Alaska. The historical context of seismic activity in the region, driven by the interaction of multiple geological structures and tectonic plates, highlights the necessity for continuous monitoring and understanding of these phenomena to mitigate risks associated with such natural events.
Original Source: earthquake.alaska.edu
