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Research > Earthquakes > Anchorage Wakes to 5.1 Quake; 2002
Anchorage Wakes to 5.1 Quake; 2002 Print this articlePrint this article
by Don Hunter
A sudden shift in the earth deep beneath Anchorage on Wednesday morning jolted the city twice, startling residents, briefly knocking out an airport ground radar system and shattering some dishes and windows.

The earthquake apparently caused little real damage, but quickly became the prime topic of conversation across town.

The Alaska Earthquake Information Center in Fairbanks said the first shake at 8:18 a.m. was a magnitude 5.1 that occurred about 22 miles down. It was followed 45 seconds later by an aftershock about 17 miles deep that measured 4.9.

Although earthquakes of similar magnitude strike Alaska routinely, these jolts were unusually strong in Anchorage because they were centered directly under the city, scientists said.

Four hours after the event, Frances Dunn in the municipal clerk's office in downtown Anchorage still had her coat handy.

"My eyes were big, and I was ready to get out," said Dunn, who with a few other City Hall employees made their way down a stairwell and into the parking lot outside when the building shook. "I wasn't here in 1964, but this is the most powerful one I've ever felt in the 27 years I've been here."

At the Sunrise Grill and Pancake House in Midtown, waitress Memory Moore said the first shake didn't alarm her too much.

"But the second one -- I thought it was going to turn the pie case over," she said.

On the 13th floor of BP Exploration (Alaska) Inc.'s high rise, the quake announced itself with a sharp jolt that rattled blinds and pictures on walls, followed by continued, gentler shaking, said company spokesman Ronnie Chappell.

"There were some folks urging folks to climb under their desks," he said. "A lot of us who kind of wanted to maintain our dignity walked to the core of the building and found a door frame, which is what we're trained to do. We probably do an earthquake drill every year."

Downtown, Cheryl Jones was working in the appellate clerk's office on the fourth floor of the state courthouse on Fourth Avenue.

"Wow, it was just, it was very long," Jones said. "The building was just basically kind of rocking. It was a really powerful shake."

Just up the street, the tremors interrupted a House Education Committee teleconference. Legislative Information Office staffer Lana Decker said she and several co-workers moved into the stairwell.

"I thought something was going to happen," Decker said. "I've lived here 20 years, and it's the worst I've ever felt."

Science tends to back up that perception. Niren Biswas, a University of Alaska Fairbanks geophysicist who is piloting a ground-motion study in Anchorage, said the two funny pictures jolts were the strongest measured here in the five years he has been collecting data. His sensors are arrayed in 35 locations around Anchorage.

State seismologist Roger Hansen said Wednesday's earthquake is the usual kind for Alaska: It occurred in the subduction zone that runs beneath Southcentral Alaska and out the Aleutian chain. Along that arc and miles below the surface, the Pacific tectonic plate is gradually, over thousands of years, sliding under the North American plate.

"So far, it doesn't look like there is anything unexpected," Hansen said Wednesday afternoon.

Tom Sokolowski, director of the Alaska Tsunami Warning Center in Palmer, said the tremors were felt from Willow to Moose Pass and were followed later in the day by several much smaller aftershocks that largely went unnoticed. People reported items knocked off shelves and minor damage in Palmer and Wasilla as well as Anchorage, he said.

The shake knocked out a ground radar system that air traffic controllers at Ted Stevens Anchorage International Airport use to keep track of surface traffic, FAA spokeswoman Joette Storm said. The radar was restored after a short time; Storm said she didn't believe any takeoffs or landings were affected.

Local and national spokesmen for Allstate Insurance Co. said they had not received damage reports from any of their clients.

Alaska State Troopers, Anchorage police and the city's emergency management office said they, too, had received few reports of damage.

"We've heard about some minor things, pictures askew, things falling off shelves, a few broken windows," said Peggy Boston, an administrative officer with the emergency management agency. "It was a pretty good jolt; we definitely ducked (under desks) and covered and held on, especially on the second one."

Boston said she hopes the early morning tremors remind Anchorage residents that they live in the heart of an active earthquake zone and that they need to be prepared for bigger shakes that are certain to happen.

Police spokesman Ron McGee said officers responded to about 10 burglar or motion alarms set off by the earthquake, not an unusually large number for such an event.

Troopers spokesman Greg Wilkinson, in a basement office in the agency's Tudor Road complex not far from the epicenter, said he didn't realize a quake had occurred until co-workers mentioned it.

"I heard this rumbling sound and walked into another office," Wilkinson said. "And a guy said, Did you feel that?' It was the talk of the building."

Reporter Don Hunter can be reached at 907 257-4349 or dhunter@adn.com. The Associated Press contributed to this story.

Anchorage Daily News, Feb. 2002


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