Overview of the Recent Earthquake Near Glennallen, Alaska

A magnitude 1.7 earthquake struck 45 miles SW of Glennallen, Alaska, on November 26, 2024, at a depth of 12.4 miles. The event has not yet been reviewed by seismologists and reflects the ongoing seismic activity in Southcentral Alaska due to its unique tectonic environment.

On November 26, 2024, a minor earthquake measuring 1.7 on the Richter scale occurred approximately 45 miles southwest of Glennallen, Alaska. The event registered at 12:37:40 AKST (21:37:40 UTC) and had a depth of 12.4 miles (20 km). As of this report, the earthquake has not undergone review by a seismologist. Its geographical impact covers various locations including Pump Station 11 and Copper Center, with significant distances from Valdez and Anchorage, among others. Such seismic activities are common in Southcentral Alaska, influenced by the complex tectonic features present in the region.

The tectonic landscape of Southern Alaska is characterized by several important geological features that contribute to its seismic activity. The primary cause of strong earthquakes in this area is the megathrust fault between the Pacific Plate and the North American Plate, with historical events such as the 1964 M9.2 Great Alaska Earthquake exemplifying this risk. In addition, intermediate-depth seismic events occur within the Wadati-Benioff Zone, where the Pacific Plate subducts, and notable instances include the Anchorage and Iniskin earthquakes in recent years. Crustal seismicity also arises from various geological structures in the Cook Inlet basin, including the Castle Mountain Fault which has been responsible for several significant tremors.

The recent earthquake near Glennallen, while minor, reflects the ongoing seismic risks present in Southcentral Alaska due to the region’s complex tectonics. Understanding the geological settings, including the megathrust fault and crustal seismicity, is essential for comprehending the potential for future earthquakes and their impacts on infrastructure and communities. Continued monitoring by seismologists is crucial to enhance preparedness and response strategies for seismic events in this geologically active region.

Original Source: earthquake.alaska.edu