A significant earthquake measuring 6.0 on the Richter scale shook the greater Anchorage area Thursday morning, marking the strongest seismic event in south central Alaska in more than three years.
The U.S. Geological Survey recorded the earthquake at approximately 8:11 a.m. Alaska time. The temblor originated at a depth of 69 kilometers, or roughly 43 miles below the surface, with its epicenter located about 12 kilometers west-northwest of Susitna, Alaska.
Susitna sits approximately 67 miles northwest of Anchorage, placing the earthquake’s origin point in a relatively remote area compared to the metropolitan region where most residents felt the shaking. The depth and distance from population centers likely reduced the intensity of ground motion experienced in urban areas.
Initial assessments indicated no significant structural damage in the Anchorage area or surrounding communities. Buildings designed to withstand seismic activity, which is standard construction practice in Alaska, appeared to perform as intended during the event.
The U.S. Tsunami Warning System quickly determined that the earthquake posed no tsunami threat to coastal areas. The depth and inland location of the epicenter made ocean wave generation unlikely, allowing officials to rule out evacuation orders for shoreline communities.
Residents throughout the Anchorage metropolitan area reported feeling moderate to strong shaking that lasted several seconds. Social media activity surged immediately after the earthquake as people compared experiences and checked on family members in different parts of the region.
Alaska holds the distinction of being the most earthquake-prone state in the United States. The state’s position along the Pacific Ring of Fire, where the Pacific tectonic plate subducts beneath the North American plate, creates ideal conditions for frequent seismic activity.
According to the U.S. Geological Survey, Alaska ranks among the most seismically active regions globally. The state experiences thousands of earthquakes annually, though most register too small for humans to feel. Magnitude 7 earthquakes occur in Alaska almost every year, demonstrating the scale of tectonic forces at work beneath the state.
Thursday’s 6.0 magnitude earthquake represents the largest seismic event to affect south central Alaska since 2021. That previous earthquake similarly shook the region without causing major damage, thanks in part to building codes that require earthquake-resistant construction.
The 2018 magnitude 7.1 earthquake that struck Anchorage remains fresh in many residents’ memories. That event caused significant damage to roads, buildings, and infrastructure, prompting updates to emergency preparedness plans and building standards.
Aftershocks commonly follow earthquakes of this magnitude, though the U.S. Geological Survey had not reported any significant secondary tremors in the immediate hours following Thursday’s event. Seismologists typically monitor affected regions closely for days or weeks after major earthquakes to track any continuing tectonic adjustments.
Alaska’s emergency management agencies maintain robust earthquake response protocols given the state’s seismic reality. Schools, hospitals, and public buildings regularly conduct earthquake drills, and most Alaskans keep emergency supply kits at home and in vehicles.
The earthquake occurred during morning hours when many residents were preparing for work or school. This timing meant most people were at home or in transit rather than in potentially more vulnerable situations like large gatherings or critical infrastructure facilities.
Anchorage International Airport reported normal operations following the earthquake, with no damage to runways or terminals. The facility’s seismic resilience reflects Alaska’s stringent infrastructure standards designed to maintain function even during significant earthquakes.
Utility companies reported no major disruptions to power, water, or natural gas service. Some customers may have experienced brief interruptions as automated safety systems checked for damage before restoring full service.
The Alaska Earthquake Center continues monitoring seismic activity in the region and will provide updates if conditions change or additional significant earthquakes occur.
