A first of its kind study that modeled oil slick weathering over time in a laboratory setting provides evidence that evaporation combined with sinking of the heavy components of surface-spill slicks can explain the presence of oil on the sea floor. This critical proof-of-concept addresses the ongoing controversy regarding the large amounts of oil found at the bottom of the Gulf of Mexico and will impact future oil slick modeling and clean-up strategies. The study is published in Environmental Engineering Science, a peer-reviewed journal from Mary Ann Liebert, Inc., publishers. The article is available free on the Environmental Engineering Science

 

Christopher Clayton Stevens, Louis Thibodeaux, Edward Overton, et al., Louisiana State University, Baton Rouge, used laboratory-scale and mathematical modeling methods to show that after a certain amount of evaporation had taken place and the slick reached a critical density and it's buoyancy relative to the water changed. Droplets comprising heavy oil residues then formed underneath the slick, broke away, and sank to the sea floor.