Scientists have discovered enormous plumes of oil in the deep waters of the Gulf of Mexico, in an indication that the leak from an underwater well could be far worse than previously estimated, The New York Times reported late Saturday.
One of the plumes was 10 miles (16 kilometers) long, three miles wide and 300 feet (91 meters) thick, according to the newspaper.
The BP-leased Deepwater Horizon oil rig exploded and sank in the gulf last month, rupturing a riser pipe that has been spewing hundreds of thousands of gallons of crude into the sea each day.
"There's a shocking amount of oil in the deep water, relative to what you see in the surface water," the Times quoted University of Georgia researcher Samantha Joye as saying.
"There's a tremendous amount of oil in multiple layers, three or four or five layers deep in the water column."
Joye is involved in one of the first scientific missions to gather details about the environmental disaster.
The plumes are depleting the oxygen in the gulf, prompting fears that the process could eventually kill much of the sea life near the plumes, the report said.
Joye said the oxygen had already dropped 30 percent near some of the plumes.
"If you keep those kinds of rates up, you could draw the oxygen down to very low levels that are dangerous to animals in a couple of months," she is quoted as saying. "That is alarming."
The oil plumes were discovered by scientists from several universities working aboard the research vessel Pelican, which sailed from Cocodrie, Louisiana, on May 3, the Times said.
Studying video of the gushing oil well, the scientists have tentatively calculated that it could be flowing at a rate of 25,000 to 80,000 barrels of oil a day, the paper noted, up to 16 times the rate of 5,000 barrels a day estimated earlier by US officials and BP.
Explore further: Spain defends Canaries oil drilling plan