ANCHORAGE (AP) - Two sharp earthquakes jolted downtown Anchorage early Wednesday, knocking items off shelves, setting off alarms and causing downtown buildings to shudder. But there were no immediate reports of damage or injuries.
Alaska Earthquake Information Center
"It's just one of those things that reminds you you live in Alaska," said Bruce Turner of the Alaska Tsunami Warning Center in Palmer.
The tsunami center estimated the preliminary magnitude for both quakes at 4.8. Both were centered about 10 miles southeast of the city. The first quake, hit at 8:18 a.m. and the second followed one minute later.
The Alaska Earthquake Information Center in Fairbanks put the magnitude of the first quake at 5.1 and estimated the second at about 5.3, said seismic data analyst Ed Clark. Clark said the quake was centered 4 miles southeast of Anchorage.
The temblors gave an early morning wakeup call to residents from Talkeetna, 85 miles north of Anchorage, to Moose Pass, 65 miles southeast of the city, said Tom Sokolowski, head of the tsunami center.
The quakes shook things up at the Sunrise Grill and Pancake House in Midtown Anchorage, said waitress Memory Moore.
"The first one wasn't bad, but the second one -- I thought it was going to turn the pie case over. It was a jolter. I ran and got underneath the door frame," Moore said. "The pies were shaking and the lights were swaying."
At the Downtown Deli, pots and pans swayed, and the ground shook, said delivery driver Chris Costanious.
"I was at the deli counter when the boss asked me if I felt the first one. I said 'nope,"' Costanious said. "Then the other one hit. That one I did feel. Everyone felt it."
Security cameras shook violently inside a Tesoro 2-GO mart in the city's Government Hill section, about a mile from downtown. Store manager Laura Sartin said she was still at home in apartments just east of the store when the quake hit.
"I thought someone crashed a car into the building," she said. "Then I felt the second one rumbling up and I knew it was no car crash."
The quake was not strong enough to generate a tsunami, according to the tsunami warning center.
While earthquakes with a magnitude of 5 are generally considered moderate, the quake was felt sharply because it was fairly shallow, occurring at a depth of about 17 miles below the Earth's surface, Sokolowski said.
"If it's shallow you're going to have a lot of energy imparted to surface structures, like houses," Sokolowski said.
An earthquake of magnitude 3.5 can cause slight damage in the local area; 4 can cause moderate damage; 5 considerable damage and 6 severe damage. Damage is usually less in areas with strong building codes.
Alaska has more earthquakes than any other area in North America, with as many as 5,000 recorded each year, according to the Alaska Earthquake Information Center in Faibanks. Most are so small they are detectable only by seismic sensors.
The 1964 Good Friday earthquake in Alaska has been estimated at 9.2. That quake and the tsunami it generated, killed 131 people.
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