Agreed. The statement also caught my eye and the only thing I could find that seems even remotely relevant is http://www.earthdrx.org/specificgravitylesser.html

Agreed. The statement also caught my eye and the only thing I could find that seems even remotely relevant is http://www.earthdrx.org/specificgravitylesser.html http://www.earthdrx.org/specificgravitylesser.html. This is very specific to lighter fluids injected into a subsurface ground layer below a water layer, and theorizes as to why the lighter fluid may not percolate through the heavier fluid above.