A magnitude 7.9 earthquake pounded a remote area of Alaska's interior, shutting down the Trans-Alaska Pipeline, opening 6-foot-wide cracks in highways and making lakes ripple as far away as Louisiana, according to press reports.The quake was one of the strongest ever recorded in the United States, but only one minor injury was reported; a woman suffered a broken arm.

The quake, centered on the Denali Fault 90 miles south of Fairbanks, struck Sunday at 1:13 p.m. Alaska Standard Time (5:13 p.m. EST) - its effects strongly felt in Anchorage about 270 miles to the south. It lasted at least 30 seconds.

Crews manually shut down the pipeline after the quake, and it was still out of service early Monday. The oil flow can be stopped for maintenance or other reasons without affecting oil deliveries because reserves are stored in tanks at the shipping terminal in Valdez.

Meanwhile, numerous roads developed wide cracks, including the Alaska Highway near Northway, about 250 miles southeast of Fairbanks.

The Richardson Highway, which parallels the pipeline between Valdez and Fairbanks, was closed near Paxson because of gaps 2 to 6 feet wide and 5 feet deep, state troopers spokesman Greg Wilkinson said. About 20 miles north, the ground on one side of the highway dropped more than 2 feet.

The worst reports of damage were along a two-mile stretch of the Tok Cutoff, which had numerous rock slides and hundreds of yards of 6-foot openings.

Fuel tanks were knocked over in Slana, a village with no electric utility. Families use diesel fuel to power generators.

At Porcupine Creek, Randy Schmoker's 150-pound anvil slid 20 feet across the floor of his metal working shop. ''A charging brown bear I can handle. This scared the hell out of me,'' Schmoker said. He expected the ground to crack open as it rippled with a series of 8-inch waves in front of him. ''They looked like ocean waves.''