Article courtesy of Staff of Science 2.0 | May 31st, 2016 | Science 2.0 | Shared as educational material.
After the 2010 Deepwater Horizon oil spill, oil contaminants such as black carbon from burning oil slicks, and contaminants from drilling mud have lingered in the subsurface of the water even though the contaminants in the surface had been swept away. These contaminants are now combining with marine debris and making a dash for the seabed. Here, it is said to affect the lives of sea creatures in a negative way. The discoveries suggest that the ecological consequences of the spill are going to be more than what was thought originally.
Some researchers believe that the oil contaminants that were found on the sea floor came from natural oil seeps, but Beizhan Yan of the Lamont-Doherty Earth Observatory, an environmental chemist who is lead author of the study on the recent findings, believe that the hydrocarbons in the water are from the crude oil that originated at the Deepwater Horizon Site. How? He claims that the presence of two compounds, barium and olefin, are what suggest the contaminants’ relation with the oil spill. Both these compounds are key components in drilling mud.
The study that Yan had done also uncovers the reason why the hydrocarbons have remained in the water column for such a long time. As Yan states, hydrocarbons, especially heavier ones, were absorbed tightly to fine particles which can stay in the water for a long time. The sea’s microorganisms accumulate these particles and carry them over to the seabed. This is how, Yan explains, oil can sink. There could be millions of gallons oil spread out on the seafloor.
What was the Deepwater Horizon Oil Spill? In the summer months od 2010, two hundred million gallons of crude oil had been blown into the Gulf of Mexico, creating the biggest marine oil spill in U.S. history. Some of the oil was recovered, burned, or broken down by bacteria. Unfortunately, one-fourth of the oil went unaccounted for and went undetectable. At the time of the spill, the travel of hydrocarbons to the ocean floor was not well understood, hence the matter was not looked to. To read more about the issue and the new discoveries click here.