There are few people who can claim direct knowledge of the ocean floor, at least before the invention of the spill-cam, last year's strangely compulsive live feed of the oil billowing out of BP's blown-out well in the Gulf of Mexico. But for Samantha Joye it was familiar terrain. The intersection of oil, gas and marine life in the Mississippi Canyon has preoccupied the University of Georgia scientist for years. So one year after an explosion on the Deepwater Horizon offshore drilling rig, about 40 miles off the coast of Louisiana, killed 11 men and disgorged more than 4m barrels of crude, Joye could be forgiven for denying the official version of the BP oil disaster that life is returning to normal in the Gulf.

The view from her submarine is different, and her attachment is almost personal. On her descent to a location 10 miles from BP's well in December, Joye landed on an ocean floor coated with dark brown muck about 4cm deep. Thick ropes of slime draped across coral like cobwebs in a haunted house. The few creatures that remained alive, such as the crabs, were too listless to flee. "Most of the time when you go at them with a submarine, they just run," she says. "They weren't running, they were just sitting there, dazed and stupefied. They certainly weren't behaving as normal." Her conclusion? "I think it is not beyond the imagination that 50% of the oil is still floating around out there."