About six to 10 million gallons of oil have been found resting on the sea floor of Gulf of Mexico. The huge amount of oil was one of the impact of the 2010 BP oil spill, which spilled some 200 million gallons of crude oil that day. According to a new study, the oil spill did not get thoroughly cleaned up and it settled on the Gulf's bottom.

Based on the new study helmed by Florida State University, researchers discovered at least 6 to 10 million gallons of oil buried in the sediment at the bottom of the Gulf of Mexico. Salon reported the oil covered a 9,300 square mile area southeast of the Mississippi Delta.

The latest findings about the millions of gallons of oil was published in the Environmental Science and Technology journal. ThinkProgress.org revealed the study sought to determine two significant things - one, whether the oil had in fact settled and two, how much of it had settled.

Florida State University's Oceanography professor and lead author of the study, Jeff Chanton said he thought the massive amount of oil at the ocean floor would be much greater since oil clumping had been observed at the sea's surface after the spill.

To locate the remaining oil, Chanton and his colleagues used carbon 14, a radioactive isotope used as an inverse tracer. As explained by Nature World News, oil does not have carbon 14 so it made the oil-containing sediment immediately stand out. Moreover, the group used geographic information system mapping to see where the oil-slicked sediment was scattered on the sea floor.

The millions of gallons of oil settling to the Gulf's bottom would actually be beneficial in the short term. But in distant future, Chanton said it will surely be a problem and it will not be good for local marine life.

"This is going to affect the Gulf for years to come," Chanton said in a statement. "Fish will likely ingest contaminants because worms ingest the sediment, and fish eat the worms. It's a conduit for contamination into the food web."

Additionally, the oil spill has already been linked to skin lesions in bottom-dwelling fishes, unhealthy corals, a decline in Kemp's ridley sea turtles, and dolphins with hormone abnormalities.

Just because the millions of gallons of oil has been buried does not necessarily mean it's forever gone. Phys.org cited there is less oxygen on the bottom of the ocean and once the oil particles start receiving less oxygen, it becomes more difficult for bacteria to decompose the oil. Thus, creating some environmental concerns for the Gulf.