Great Unkowns in Gulf Oil Spill

Any oil in the deep-sea environment could persist for a long time. The majority of oil on the surface evaporates, washes up on shore, or is degraded by natural weathering and oil-eating microbes. In the deep sea, on the other hand, it's dark and still, meaning no weathering and no evaporation. Microbial degradation is pretty much the only mitigating process—but it's slow. As a result, there's some possibility that deep-sea oil could get churned up by storms and have a limited shoreline impact sometime in the future, Joye says.
Newsweek Magazine
http://www.newsweek.com/