Samples taken from the seafloor near BP’s blown-out wellhead indicate miles of murky, oily residue sitting atop hard sediment. Moreover, inside that residue are dead shrimp, zooplankton, worms and other invertebrates.

“I expected to find oil on the sea floor,” Samantha Joye, a University of Georgia marine sciences professor, 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.”

The scientists aboard the research vessel Oceanus suspect it’s all from the BP spill, but will have to wait until they return to shore this week to confirm it’s the same oil source.

“It has to be a recent event,” Joye said. “There’s still pieces of warm bodies there.”

If it is BP oil, it could undermine the federal government’s estimate that 75 percent of the spill either evaporated, was cleaned up or consumed by natural microbes.

What the scientists do already know is that the oil is not coming naturally from below the surface.

“What we found today is not a natural seep,” Joye wrote in her blog on Sept. 5 when the first surprise sediment was found.