At least three and as many as nine oil wells were burning yesterday in Iraq’s Rumaila oil field, just north of the Kuwait border. News of the fires caused an abrupt spike in global oil prices, but the market settled down after Bush administration officials said the damage appeared to be limited. The Rumaila field is capable of producing more than 700,000 barrels per day, and the Bush administration has explicitly warned Iraq against destroying that field and others, saying the oil represents the nation’s best chance of rebuilding its economy after the war. It is unclear whether fires are also burning in other fields north of Baghdad, whether more fires will be set, and how extensive the environmental harm will be. “The concern about long-term damage is pure speculation until we see something definitive,” said Anthony Cordesman, a former Defense Department official and current senior research fellow at the Center for Strategic and International Studies.