Scientists funded by the National Science Foundation (NSF) and affiliated with the Woods Hole Oceanographic Institution (WHOI) have detected a plume of hydrocarbons at least 22 miles long and more than 3,000 ft below the surface of the Gulf of Mexico, a residue of the BP Deepwater Horizon oil spill. The 1.2-mile-wide, 650-ft-high plume of trapped hydrocarbons was detected during a ten day subsurface sampling effort from June 19-28, 2010 near the wellhead. The results provide a snapshot of where the oil has gone as surface slicks shrink and disappear.