From US News & World Report: Where's the Oil? On the Gulf Floor, Scientists Say
NEW ORLEANS—Far beneath the surface of the Gulf of Mexico, deeper than divers can go, scientists say they are finding oil from the busted BP well on the sea's muddy and mysterious bottom.
Oil at least two inches thick was found Sunday night and Monday morning about a mile beneath the surface. Under it was a layer of dead shrimp and other small animals, said University of Georgia researcher Samantha Joye, speaking from the helm of a research vessel in the Gulf.
The latest findings show that while the federal government initially proclaimed much of the spilled oil gone, now it's not so clear.
At these depths, the ocean is a cold and dark world. Yet scientists say that even though it may be out of sight, oil found there could do significant harm to the strange creatures that dwell in the depths—tube worms, tiny crustaceans and mollusks, single-cell organisms and Halloween-scary fish with bulging eyes and skeletal frames.
"I expected to find oil on the sea floor," Joye said Monday morning in a ship-to-shore telephone interview. "I did not expect to find this much. I didn't expect to find layers two inches thick. It's weird the stuff we found last night. Some of it was really dense and thick."
Joye said 10 of her 14 samples showed visible oil, including all the ones taken north of the busted well. She found oil on the sea floor as far as 80 miles away from the site of the spill.
"It's kind of like having a blizzard where the snow comes in and covers everything," Joye said.
And the look of the oil, its state of degradation, the way it settled on freshly dead animals all made it unlikely that the crude was from the millions of gallons of oil that naturally seep into the Gulf from the sea bottom each year, she said. Later this week, the oil will be tested for the chemical fingerprints that would conclusively link it to the BP spill.
"It has to be a recent event," Joye said. "There's still pieces of warm bodies there."
Since the well was capped on July 15 after some 200 million gallons flowed into the Gulf, there have been signs of resilience on the surface and the shore. Sheens have disappeared, while some marshlands have shoots of green. This seeming recovery is likely a result of massive amounts of chemical dispersants, warm waters and a Gulf that is used to degrading massive amounts of oil, scientists say.
Animal deaths also are far short of worst-case scenarios. But at the same time, a massive invisible plume of oil has been found under the surface, shifting scientists' concerns from what can be easily seen to what can't be.
For Ian MacDonald, a Florida State University biological oceanographer who wasn't part of Joye's team, the latest findings confirm that government assessments about how much oil remains—especially a report on the subject by the National Oceanic and Atmospheric Administration in August—were too optimistic.
The oil "did not disappear," he said. "It sank."
Not all scientists agree with this assessment.
Ed Overton, a Louisiana State University chemist who has analyzed the spill for NOAA, doubted much oil was resting on the bottom. He said the heavier components in oil—the asphalts—make up only about 1 percent of the oil that was spilled.
And Roger Sassen, an organic geochemist at Texas A&M University who has studied natural oil seeps, said so much oil seeps naturally into the Gulf each year that it's hard to argue that the BP spill will make a significant difference.
Nonetheless, the big questions now are exactly how much oil is at the bottom and how many organisms are being exposed to it, said Robert Carney, an oceanographer and deep-sea expert at Louisiana State University. The answers to those questions could shed some light on the unseen damage to wildlife from the oil spill.
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