The size of the quake was originally reported to have been a magnitude of 7.4, but has been revised to a 7.5, said Paul Caruso, a geophysicist with the U.S. Geological Survey. He said an earthquake of this size, in this area, is not a surprise.
"This is an area where the Pacific Plate is subducting underneath the North American Plate. And because of that, the Pacific Plate actually goes underneath the North American Plate, where it melts," Caruso said, noting that's why there are volcanoes in the region. "And so we commonly have large, magnitude 7 earthquakes in that area."
Public safety officials in King Cove sent out an alert urging residents in the coastal area to move inland to higher ground. Some schools in the Kenai Peninsula Borough School District were evacuating to higher ground, the district said on Twitter.
The tsunami warning was issued by the National Tsunami Warning Center, following an earthquake off Sand Point, Alaska. The National Tsunami Warning Center in Palmer, Alaska, said the tsunami warning was in effect for roughly 950 miles (1,529 kilometers), from 40 miles (64 kilometers) southeast of Homer to Unimak Pass, about 80 miles (129 km) northeast of Unalaska.
The Alaska Earthquake Center said the quake was widely felt in communities along the southern coast, including Sand Point, Chignik, Unalaska and the Kenai Peninsula. The Alaska Earthquake Center said a magnitude 5.2 aftershock was reported 11 minutes later, centered roughly in the same area.
"It was a pretty good shaker here," said David Adams, co-manager of Marine View Bed and Breakfast in Sand Point. "We're doing OK." He said all guests were accounted for and "the structure itself is sound."
"You could see the water kind of shaking and shimmering during the quake," he said. "Our truck was swaying big time." He didn't take any photos or video: "It just kind of happened of all of a sudden."
Rita Tungul, front desk assistant at the Grand Aleutian Hotel in Unalaska, said she felt some shaking but it wasn't strong. Her coworker didn't feel the quake at all, she said.
Unalaska officials sent out a message saying the city is just outside the warning zone and they aren't ordering evacuations right now. Unalaska public safety officials earlier Monday had sent out a release saying they would be conducting tests of the community's tsunami warning sirens.
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