A powerful earthquake measuring magnitude 6.3 struck the Andreanof Islands in Alaska at 19:57 UTC on December 8, 2024. The earthquake occurred at a depth of 18 km (11 miles), according to the United States Geological Survey (USGS), which has issued a Green alert for shaking-related fatalities and economic losses. The same magnitude and depth were confirmed by the European-Mediterranean Seismological Centre (EMSC).
The epicenter of the earthquake was located approximately 107 km (66 miles) south-southwest of Adak, Alaska, and 1,540 km (957 miles) east-southeast of Klyuchi, in Russia’s Kamchatka Peninsula. The region is known for seismic activity, and despite the strength of the quake, no tsunami threat has been issued by the National Weather Service’s Pacific Tsunami Warning Center (NWS PTWC).
Aftershocks and Further Activity
The initial quake was followed by a series of aftershocks, including a magnitude 4.3 event at 20:01 UTC, a magnitude 3.9 at 20:09 UTC, and another 3.7 tremor at 20:13 UTC. These aftershocks suggest ongoing seismic activity in the region, though the likelihood of significant damage remains low.
Potential Impact and Preparedness
The USGS has assessed that while the earthquake was strong, the population in this region largely resides in structures that are built to withstand earthquake shaking. However, there are still vulnerable buildings in the area, such as unreinforced brick masonry and some types of reinforced masonry structures. The assessment suggests that the likelihood of fatalities or major economic losses is low due to the resilience of the local infrastructure, although there may be localized damage in areas with weaker buildings.
Context of Seismic Activity
This event marks the second magnitude 6+ earthquake to occur on December 8, 2024, after a magnitude 6.1 earthquake struck the Kuril Islands off the coast of Russia at 10:25 UTC. The region around the Andreanof Islands, part of the larger Aleutian Islands chain, is seismically active due to the tectonic interactions between the Pacific and North American plates. Earthquakes of this magnitude are not uncommon in the area, although significant damage from such events is rare, thanks to robust building codes and preparedness measures.
As of now, there are no reports of casualties or extensive damage, and local authorities continue to monitor the situation.
