Alaska Gov. Walker issues disaster declaration after major earthquake damages infrastructure near Anchorage

  • A large earthquake has rocked buildings in Anchorage, prompting people to run out of offices and seek shelter under office desks.
  • The U.S. Geological Survey says the earthquake was centered about 7 miles north of Alaska's largest city.
A vehicle lies stranded on a collapsed roadway near the airport after an earthquake in Anchorage, Alaska, U.S. November 30, 2018. 
Nathaniel Wilder | Reuters
A vehicle lies stranded on a collapsed roadway near the airport after an earthquake in Anchorage, Alaska, U.S. November 30, 2018. 

A large earthquake has rocked buildings in Anchorage and caused lamp posts and trees to sway, prompting people to run out of offices and seek shelter under office desks.

The U.S. Geological Survey said the magnitude of the earthquake was 7.0, after initially giving a preliminary magnitude of 6.7.

Gov. Bill Walker issued a disaster declaration in the aftermath.

No tsunami danger exists for the U.S. west coast, British Columbia and Alaska, according to the US National Tsunami Warning Center. The center had initially issued a tsunami warning for coastal zones of southern Alaska.

Michael Burgy, a senior technician with the National Tsunami Warning Center in Palmer, Alaska, said the tsunami warning was automatically generated based on the quake's size and proximity to shore. Scientists monitored gauges to see if the quake generated big waves. Because there were none, they canceled the warning.

USGS says the earthquake Friday morning was centered about 7 miles (12 kilometers) north of Alaska's largest city, with a population of about 300,000. There were no immediate reports of any deaths or serious injuries.

People went back inside buildings after the earthquake but a smaller 5.8 magnitude aftershock a short time later sent them running back into the streets again.

Cracks could be seen in a two-story downtown Anchorage building, and photographs posted to social media showed fractured roads and collapsed ceiling tiles at an Anchorage high school. One image showed a car stranded on an island of pavement, surrounded by cavernous cracks where the earthquake split the road.

Cereal boxes and packages of batteries littered the floor of a grocery store, and picture frames and mirrors were knocked from living room walls.

All flights were halted at the airport after the quake knocked out telephones and forced the evacuation of the control tower, and the 800-mile Alaska oil pipeline was shut down while crews were sent to inspect it for damage.

Anchorage's school system canceled classes and asked parents to pick up their children while it examined buildings for gas leaks or other damage. Officials opened an Anchorage convention center as an emergency shelter.

Alaska averages 40,000 earthquakes per year, with more large quakes than the other 49 states combined.

Southern Alaska has a high risk of earthquakes due to tectonic plates sliding past each other under the region. According to the U.S. Geological Survey, the Pacific plate is sliding northwestward and plunges beneath the North American plate in southern Alaska, the Alaska Peninsula and the Aleutian Islands.

Alaska has been hit by a number of powerful quakes over 7.0 magnitude in recent decades, including a 7.9 that hit last January southeast of Kodiak Island. But it is rare for a quake this big to strike so close such a heavily populated area.

On March 27, 1964, Alaska was hit by a magnitude 9.2 earthquake, the strongest recorded in U.S. history, centered about 75 miles (120 kilometers) east of Anchorage. The quake, which lasted about 4½ minutes, and the tsunami it triggered claimed about 130 lives.

President Donald Trump, who is in Argentina for the G-20 summit, tweeted about the earthquake and told Alaskans "Your Federal Government will spare no expense."

NBC affiliate KTUU was knocked off the air due to the quake, according to NBC News. A reporter at KTVA, a CBS affiliate, tweeted a picture of its damaged newsroom.

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