Wailing sirens prompted residents to seek higher ground in communities along Alaska’s southern coast after a reported 7.5 magnitude earthquake that shook buildings triggered a tsunami warning Monday.
The quake was centered near Sand Point, a city of about 900 people off the Alaska Peninsula where wave levels hit 2 feet, according to the National Tsunami Warning Center. The warning was downgraded to an advisory just over two hours after the quake.
Patrick Mayer, superintendent of the Aleutians East Borough School District, said parents picked up children from Sand Point School, which also served an evacuation point. He said a school bus also was sent to a fish processing facility to bring workers to the school.
“We’re on very high ground,” he said. Mayer wasn’t aware of any structural damage and said officials planned to reopen school normally on Tuesday.
The quake struck in the North Pacific Ocean just before 1 p.m. It was centered about 67 miles (118 kilometers) southeast of Sand Point, according to the Alaska Earthquake Center. The community is about 800 miles (1,288 km) southwest of Anchorage. The quake was recorded at a depth of 19 miles (30 kilometers).
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 quake was widely felt in communities along the southern coast, including Sand Point, Chignik, Unalaska and the Kenai Peninsula, according to the Alaska Earthquake Center, which said a magnitude 5.2 aftershock was reported 11 minutes later, centered roughly in the same area.
Sand Point School, with 130 students, is the only school in the community, Mayer said, but he said the four other schools in the district felt the quake to varying degrees. The closest school is 90 miles away, he said.
Some schools in the Kenai Peninsula Borough School District were evacuating to higher ground, the district said on Twitter.
Public safety officials in King Cove sent out an alert urging residents in the coastal area to move inland to higher ground.
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.”
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.
“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 all of a sudden.”