Researchers studying the effects of the 2010 BP oil spill have found an oily "bathtub ring" the size of Rhode Island on the sea floor.
An estimated 172 million gallons of oil spilled into the Gulf of Mexico during the disaster, and scientists are trying to determine where it all went. A new study suggests that 84 million gallons coagulated on the sea floor around the Deepwater Horizons oil rig.
Using data from the Natural Resource Damage Assessment conducted by the National Oceanic and Atmospheric Administration, researchers found a 1,250-square-mile patch of sea floor where they believe 2 to 16 percent of the oil settled; the analysis suggests the deposits came from the Macondo well and eventually made their way to the sea floor.
BP told The Associated Press in an email that the study's authors "fail to identify the source of the oil, leading them to grossly overstate the amount of residual Macondo oil on the sea floor and the geographic area in which it is found." The authors say that while too much time has passed to do a chemical analysis, other signs — including the depth of the oil and its distance from the well — point to it coming from the BP rig.