A 8.2 magnitude earthquake occurred just off Alaska's coast late Wednesday night. It caused tremors that could have been felt across the state, and set off tsunami alarms. The epicenter of the earthquake, which was the strongest recorded in the United States in over 50 years, occurred just 50 miles off the coast of Alaska's Gulf of Alaska. Residents on the southwest peninsula shifted to higher ground after the shaking stopped. They were preparing for a tsunami.AdvertisementAdvertisementAdvertisementThe tsunami warning was issued for nearly two hours. A tsunami advisory was also in effect as far as Hawaii. However, when tsunami waves struck the shoreline at approximately 7 inches above the normal level, the threat was reduced and lifted several hours later. Although there was no significant damage to the earthquake, there were strong aftershocks. In the time period between the initial shock and the second one, the Alaska Earthquake Center recorded 14 aftershocks at magnitude 4 or greater. Two of these were magnitudes 6.2 and 5.8.Subscribe to the Slatest Newsletter Get a daily email update with the latest stories. Signing you up was not possible due to an error Please try again. To use this form, please enable jаvascript. Email address: I would like to receive updates on Slate special offers. You agree to our Privacy Policy & Terms by signing up. Thank you for signing up! You can cancel your subscription at any time.According to the U.S. Geological Survey, thrust faulting occurred at shallow depth at the subduction zone interface of the North America and Pacific plates. This is where the Pacific plate starts subducting to the northwest below Alaska. Alaska is a hotbed for seismic activity. It has recorded as many as 49,000 events in 2017 alone. However, the most recent earthquake is the third to strike Alaska in the past 18 months. In 2020, Alaska was home to the two strongest quakes anywhere in the world.