Even under the most optimistic scenarios, operations were not expected to return to normal before several days, but the markets focused on relief that a crisis had been skirted, pushing crude oil below 105 dollars a barrel for the first time since April.

As the powerful hurricane churned toward the region last week and weather forecasters predicted landfall Monday, oil companies evacuated staff from 626 of 717 offshore oil platforms, protected equipment and battened down refineries.

Gulf of Mexico oil production -- a quarter of US oil output at 1.3 million barrels a day -- was totally shut down over the weekend, according to the US Department of the Interior.

And more than 95 percent of natural gas production was cut off.

Early Tuesday, oil refining capacity was shut in by nearly three million barrels a day, 17 percent of total US refining capacity, said Andy Lipow, an oil industry expert based in Houston, Texas.

Although the oil sector had braced for Gustav's arrival with memories of Hurricane Katrina's devastation three years ago -- oil platforms toppled, refineries flooded, installations out of service for several months -- the worst appears to have been avoided.

"We didn't see much of that this time, although I will tell you that it's a little early to be making any forecasts," President George W. Bush said at a White House disaster briefing.

"There are some encouraging signs," Bush said as officials assessed damage to infrastructure.

Lipow said that "there doesn't appear to be any major damage to refiners."

"There hasn't been any flooding," he added.

A spokesman for the leading US refiner Valero, Bill Day, told CNBC business network that a team was working on the company's refinery in the New Orleans area to "make sure there's no serious structure damage" before planning the unit's reopening.

"But that's going to take a number of days," Day said.

According to Lipow, the major obstacle to getting the refineries back in business remains the lack of electricity, particularly in New Orleans.

"A number of refiners don't have power at this time," he said.

"From the time that they have the power restored and the personnel back, the smaller refiners will be running in three to five days," he predicted, with the larger refineries taking five to 10 days.

But the refineries will be dependent on the return of oil pumped offshore: not only has production been halted, but most of the ports have been closed by the US Coast Guard.

Oil giant ExxonMobil said Tuesday that it "will begin its post-storm assessment process today to start to determine if and how any of our Gulf Coast oil and gas production facilities were impacted by the storm."

Anglo-Dutch giant Royal Dutch Shell planned to fly over the Gulf to survey storm damage and put scaled-back teams back to work on platforms Tuesday.

Transocean, the world leader in offshore drilling, told AFP that planes were overflying the zone to assess the situation, but its key assets had been protected ahead of Gustav's arrival.

According to Lipow, 50 percent of the offshore production can be restarted in three to five days, "assuming no damage."

Three months after Hurricane Katrina wreaked damage in 2005, a quarter of US oil production remained cut.

RMS, a consultancy specialized in risks linked to natural catastrophes, estimated that Gustav's damage to oil installations would cost between one and three billion dollars.

Related Links
Powering The World in the 21st Century at Energy-Daily.com

Memory Foam Mattress Review

SPACE MEDIA NETWORK PROMOTIONS Solar Energy Solutions Tempur-Pedic Mattress Comparison ... Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News