Seismic Activity in the Yakutat Block: An Overview of Recent Events and Tectonic Dynamics
On June 1, 2024, at 09:45:02 AKDT (17:45:02 UTC), an earthquake was recorded with its epicenter located at coordinates 60.1670°N, 140.7157°W, at a depth of 0 miles (0 km). The seismic event, which has not yet been reviewed by a seismologist, occurred in a region characterized by significant geological activity due to the complex tectonic setting of the Yakutat Block in southern Alaska.
The earthquake’s location is detailed as being 55 miles NW of Yakutat, 59 miles E of Cape Yakataga, and extending to distances of up to 257 miles NW of Juneau. The magnitude and event type specifics were classified as an earthquake with a local magnitude scale reading (Ml2).
The Yakutat Block, where the earthquake occurred, is part of a highly active seismic belt due to the northward transportation of the Yakutat microplate along transform faults like the Queen Charlotte and Fairweather faults. This microplate’s collision with the continental margin of southern Alaska has resulted in a series of notable seismic events over the years, including two great earthquakes in 1899, the 1958 Lituya Bay Earthquake, and the 1972 Saint Elias Earthquake, among others. The region has experienced significant geological transformations due to these events, including land uplift and subsidence.
The area is known for its high level of background seismicity, with hundreds of earthquakes recorded annually, most of which are shallow and located within a 50-mile-wide coastal zone. This seismic activity is influenced by major structural features such as the Transition Fault, separating the Yakutat microplate from the Pacific Plate, and the northern Gulf of Alaska fault zone, both of which have been sites of significant earthquakes in the past.
This recent earthquake adds to the complex seismic history of the Yakutat Block, highlighting the ongoing tectonic processes that shape southern Alaska’s landscape and pose challenges for understanding and mitigating seismic risks in the region.