On April 19, 2025, a magnitude Ml earthquake occurred in Interior Alaska, with a depth of 11.0 miles. The event, located 23 miles northeast of Fox, has not been reviewed by a seismologist and occurred in a region known for its seismic activity.
Interior Alaska’s seismicity is attributed to right-lateral strike-slip faults, north-northeast-trending seismic zones, and thrust faults in the northern foothills of the Alaska Range. The region has experienced significant earthquakes in the past, including the 1937 M7.3 Salcha Earthquake, which caused ground failures but no surface rupture. Other notable events include the 1968 M7.1 Rampart, the 1985 M6.1 Dall City, and the 1995 M6.0 Minto Flats earthquakes.
The Fairbanks Seismic Zone has also seen significant seismic activity, including three M5-6 earthquakes in 1967. A M7.2 thrusting event in 1947 further indicated ongoing deformation in the region. The seismic activity decreases considerably east of longitude 146 degrees west, between the Tintina Fault to the north and the Denali Fault to the south.
Overall, Interior Alaska’s seismic activity is attributed to various tectonic structures that contribute to generating earthquakes in the region. Monitoring and understanding these events are crucial for assessing and preparing for potential seismic risks in the area.
Source
Photo credit earthquake.alaska.edu
