Alaska Jolted by Major Earthquake

FAIRBANKS, Alaska, November 4, 2002 (ENS) - A major earthquake, registering at a magnitude of 7.9, shook Central Alaska 92 miles south of Fairbanks on Sunday afternoon at 1:12 local time, according to the Alaska Earthquake Information Center in Fairbanks.

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Aerial photo of the lightly settled area of central Alaska shaken by the quake. The red line indicates the Denali fault. (Photo courtesy U.S. Geological Survey)
One of the strongest ever recorded in the United States, Sunday's quake was felt throughout Alaska and rippled across the entire continent. It caused some houseboats to slam into docks on Seattle's Lake Union 1,400 miles south of the epicenter, and rippled waters as far away as New Orleans, Louisiana.

The earthquake began on the Denali fault, and is the largest earthquake recorded on this fault since at least 1912 when a magnitude 7.2 earthquake occurred more than 50 miles to the east of Sunday's epicenter.

The temblor radiated from the same fault line as a quake of 6.7 magnitude quake that shook the area immediately to the east on October 23.

The two minute long quake Sunday cracked highways, triggered mudslides, and toppled fuel tanks.

A section of the Trans-Alaska oil pipeline was knocked off its supports at Mile 588, about 48 miles south of Delta Junction. The supports gave way although beams are embedded in gravel berms to allow large pipe movements as the pipeline crosses the Denali fault.

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Trans-Alaska Pipeline as it crosses the Denali fault (Photo courtesy Trans-Alaska Pipeline System)
The pipeline was shut down automatically with no reported loss of oil. Workers with Alyeska Pipeline Service Co. took over manual control and had the pipeline shut down down about an hour after the quake hit.

The pipeline, vital to the economy of Alaska, crosses three earthquake fault lines, including the Denali fault where Sunday's quake occurred.

The quake disrupted travel in several regions, closing an 80 mile stretch of the Richardson Highway between Delta Junction and Paxson.

A three foot wide crack opened up in the main road between Fairbanks and Anchorage, Alaska State Troopers said. The Alaska Highway is closed between mile 74 and mile 80 on the Tok Cutoff due to earthquake damage.

Today the highway at Delta Junction is open to one lane traffic, according to the Alaska Department of Transportation. Repairs have been made to the Richardson Highway at mile 258, where yesterday’s earthquake damaged the roadway, and two lane traffic is now getting through.

At the University of Alaska Fairbanks, water pipes burst in the Geophysical Institute where the Alaska Earthquake Information Center (AEIC) is housed.

Reports of light damage were received by the AEIC from communities throughout central Alaska. Only one minor injury was reported, a 76 year old Mentasta woman who broke her arm falling down stairs as she tried to leave her home.

Across the state windows cracked, household furniture rocked, and cabinets spilled their contents. In Anchorage, people watched parked cars shake and roll with each heave of the Earth.

The area around Alaska's Mount McKinley continued to shake today as five sizable aftershocks from the major earthquake rumbled through the lightly populated region.