Scientists have discovered more damage left behind in the Gulf of Mexico after BP's catastrophic Deepwater Horizon oil spill in 2010, news reports said on Tuesday. 

According to the new research, a 1,235-square-mile “bathtub ring” of oil was found on the ocean floor – which amounts to approximately 10 million gallons of oil that has settled and coagulated on the floor, said the study that was published by the National Academy of Science on Monday.    

The report was written by a team of scientists with the University of California-Santa Barbara, University of California-Irvine, and the Woods Hole Oceanographic Institute. The team collected and tested more than 3,000 samples of sediment for the chemical hepane – a component of the crude oil released by BP wells – which was taken from 534 locations in the Gulf.  

BP's Deepwater Horizon rig spilled a total of 172 million gallons of oil into the Gulf of Mexico in April of 2010. It is considered the largest marine oil spill in history. This spill left a footprint on the ocean floor approximately the size of Rhode Island, said the study. 

Researchers say the report tries to answer some of the lingering questions that have remained since the spill such as where all the oil went – after some two million barrels were never found – and how exactly the spill impacted the deep sea.    

BP has continuously tried to play down the environmental damage caused by the spill, saying that most of the unrecovered light sweet crude oil dissolved or evaporated before it reached land and that it did not settle on the ocean floor. 

BP also estimated that only 2.45 million barrels of oil were spilled in the Gulf, whereas the Justice Department, in federal court proceedings, put the number closer to 4.5 million barrels.