An Experimental Evaluation of Oil Slick Movement Caused by Waves

Abstract

The wave-induced movement of oil lenses and other floats was studied by using mechanically generated gravity waves in a water tank. The measured surface drift velocities were in all cases higher than those predicted by the Stokes theory of deep water waves. For wave conditions at which the Stokes velocity is higher than 2 cm sec?1, the measured surface velocities were 35?150% higher than the Stokes velocity. The drift velocity was insensitive to float size when the float length was larger than one wavelength. Thin, flexible, plastic floats were found to have the same drift speed as similarly sized oil lenses. A discussion of the movement of oil spills on the open ocean is included.