Jones, who's worked in the industry for more than two decades, described the crude as hard to scoop out of the water because it's so thin. Some sunshine, he said, might evaporate a good portion of it.
The amount of oil spilled so far continued to be debated. BP, which revised its estimates upward after a watchdog group quibbled with its earlier statements, said it had no working flow meters near the sea bottom to measure the flow. Coast Guard officials Saturday said it was difficult to know how much oil has spewed forth since the April 20 blast. But experts say the spill may grow to exceed the 11 million gallons that the Exxon Valdez spilled in Alaska's Prince William Sound in 1989.
The Obama administration has said no new offshore oil drilling leases will be issued unless rigs have safeguards to prevent a repeat of the explosion. But in a television appearance Sunday on "This Week," Salazar rejected calls to shut any of the remaining 30,000 drilling rigs in the gulf.
"For us to turn off those spigots would have a very huge impact on America's economy right now," Salazar said. "This is an industry that can operate safely."
Obama, accompanied by White House Chief of Staff Rahm Emanuel, domestic security and counter-terrorism advisor John Brennan and energy advisor Carol Browner, referenced Hurricane Katrina, the 2005 disaster that killed almost 2,000 people and caused tens of billions of dollars in damage. The slow federal response to Katrina helped erode the George W. Bush administration's political standing.
"I've heard already that people are understandably frustrated and frightened, especially because the people in this region have been through worse disasters than anybody should have to bear," Obama said.
He promised federal assistance, but also fingered BP.
"Let me be clear: BP is responsible for this leak. BP will be paying the bill. But as president of the United States, I'm going to spare no effort to respond to this crisis for as long as it continues," he said. "And we will spare no resource to clean up whatever damage is caused."
Times staff writer Jill Leovy in Los Angeles contributed to this report.