The Falkland Islands' quest for potentially vast quantities of hydrocarbons offshore has taken off with an exploratory drilling season after operators raised enough cash to lease a rig from Scotland.

The semisubmersible Ocean Guardian rig, in operation in the North Sea for well over 20 years, was leased by Desire Petroleum as part of an ambitious plan to explore reserves in the North Falkland Basin. Experts have said the basin could have very large reserves that could transform the Falkland Islands, a British overseas territory that was the scene of a 1982 war between Britain and Argentina, into an oil-rich nation.

Industry sources said a tug boat, Maersk Traveler, is hauling the rig from its Scottish Highlands deepwater home to the Falklands. Current estimates said the rig could be in place within two months, or slightly longer if it faced rough weather on its trans-Atlantic journey.

U.K.-based Desire Petroleum said it had launched the exploratory operation on the basis of expert estimates the basin floor may be holding more than 3.5 billion barrels of oil and more than 9 trillion cubic feet of gas.

Although no commercial discoveries have been made in the Falklands, exploration ventures go back to 1998, when six wells were drilled to the north of the islands. The drilling revealed the presence of a rich organic source rock that, estimates then said, could hold up to 60 billion barrels of oil. Although that estimate has not been scaled down, recovery of those quantities of oil may require huge investments over a long period, analysts said.

The Falklands government has put in place new environmental legislation in response to protests from campaigners who believe the arrival of oil could ruin the islands. The Falklands have a thriving tourism industry, mainly because of their main attraction -- penguins -- but officials point out the earnings from foreign travelers do not compare with a potential oil bonanza.

Critics of the development have also cited Britain's apparent failure to make good use of its North Sea oil boom and welcomed the news of oil exploration with a mixture of dismay and anxiety -- especially about Argentina's next move.

The islands were invaded by Argentina in 1982 in an ill-fated campaign to reassert their Argentine identity as Islas Malvinas. The war ended with an Argentine defeat. Emotional scars in Buenos Aires run far deeper than those felt in Britain. The conflict did, however, trigger the collapse of military supremacy in Argentina and restored democratic order.

Falklanders say they would like to know how Argentina will react next once the islands' hidden oil wealth becomes a reality. In some Falklands circles, discussion of another possible encounter with Argentina is taboo, while Argentine President Cristina Fernandez de Kirchner keeps alive the flame of her nation's "inalienable" rights over the islands with frequent pronouncements.

The change in the islands' fortune is a certainty, reinforced by operators' argument they chose the North Falkland Basin because they consider it relatively low risk in exploration terms, with both proven oil and gas. Industry analysts said the area is also cheaper to work in, as it involves modest water depths, compared to the great depths Brazil needs to drill for its new oil.