Shell Oil Co. said Thursday that it will sell all of its oil and gas production properties in Alaska and suspend drilling in the Chukchi Sea, where Shell and its partners have spent $190 million and three years exploring unsuccessfully for oil.

The moves are part of a restructuring of the financially strapped company, which earlier announced up to 4,700 layoffs and put up for sale its Wilmington refinery and other properties.

Because Shell was one of the major leaseholders in the Chukchi Sea, the action could also signal some disenchantment with drilling prospects in an area off northwestern Alaska once thought to be a prime candidate for huge oil discoveries.

"I can't call it good news," said Ken Boyd, deputy director of Alaska's Division of Oil and Gas.

Other industry officials and analysts said that interest in the area remains strong, however.

Chevron Corp., for instance, is sinking a well about 100 miles east of Shell's holdings. "We think the area has a lot of potential," said Tom Cook, exploration representative of Chevron U.S.A. in Alaska, which has taken over use of Shell's drilling rig in the Chukchi Sea.

Meanwhile, Atlantic Richfield Co., a major operator on Alaska's North Slope, is preparing to drill a well in the Cabot Prospect in the Beaufort Sea, near the shore about 25 miles east of Barrow.

Shell is selling its Middle Ground Shoal production unit in the Cook Inlet, which includes two offshore platforms and an onshore processing plant; a 33% share of the Beluga River natural gas-producing area and a 0.14% interest in the massive Prudhoe Bay oil field on the North Slope.

All told, Shell's interest in the fields amounts to daily production of 7,500 barrels of oil and 23.1 million cubic feet of gas. If the properties are sold, Shell will lay off its 50 Alaska employees and close its Anchorage office.

"If we do not get what we consider a satisfactory price, we will continue to operate these properties," Shell's Holly R. Hutchins said in Houston.

Hutchins said the actions do not mean Shell is giving up on Alaska, though analysts say it has never been a major player there.

The oil company remains a partner of Amoco Corp. in exploratory drilling on the Galahad Prospect in the Beaufort Sea. Shell also continues to hold exploration acreage in the Chukchi, the North Aleutian Basin and the North Slope. It plans to bid on leases in the Arctic National Wildlife Refuge if Congress approves drilling there.