|
|
1. Natural gas escaping through seafloor cracks off Santa Barbara, Calif.,
also bubbles up to the ocean surface. The oil seep offers a natural
laboratory for scientists to study what happens to oil in the ocean
ecosystem.
(Photo by Dave Valentine, University of California, Santa Barbara) |
2. There’s an oil spill every day off the coast of Santa Barbara, Calif.,
where oil is seeping naturally from cracks in the seafloor into the
ocean. Lighter than seawater, the oil floats to the surface. Some 20 to
25 tons of oil are emitted each day.
(Photo by Dave Valentine, University of California, Santa Barbara) |
3. In 2005, marine chemists Chris Reddy of Woods Hole Oceanographic Institution (WHOI) and Dave Valentine of the University of California, Santa Barbara, began studying the Santa Barbara oil seeps. Above, former WHOI research specialist Lary Ball (in scuba gear) collects videotape with an underwater camera while WHOI research specialist Bob Nelson (in snorkeling gear) collects oil samples.
(Photo by Chris Reddy, Woods Hole Oceanographic Institution) |
4. WHOI researcher Bob Nelson scoops up a sample of oil that leaked out of the seafloor off the coast of Santa Barbara. Analyzing the sample, they confirmed that the oil at the surface came from reservoirs beneath the seafloor.
(Photo by Chris Reddy, Woods Hole Oceanographic Institution) |
5. To track how much oil at the ocean surface sank back into mud atop the seafloor, the researchers used a sediment grab sampler to collect specimens of seafloor sediments.
(Photo by Lea Constan, University of British Columbia) |
6. WHOI shipboard technician Dave Sims guides the sediment grab sampler back on board the research vessel Atlantis with UCSB student A. J. Cecchettini (holding rope). WHOI marine chemist Chris Reddy (foreground) anxiously awaits to see what the grab sampler grabbed.
(Photo by Lea Constan, University of British Columbia) |
7. Researchers eagerly examine the seafloor mud extracted by the sediment grab sampler: from left, undergraduate student Tesfaberhan Habtemariam, UCSB graduate student Chris Stubbs, and WHOI marine chemist Chris Reddy.
(Photo by Frank Kinnaman, University of California, Santa Barbara) |
8. UCSB graduate student Frank Kinnaman and WHOI marine chemist Chris Reddy take samples of seafloor mud, which were analyzed to determine the amount and types of petroleum hydrocarbons they contained.
(Photo by Lea Constan, University of British Columbia) |
9. Chris Farwell, an undergraduate student at the University of California, Santa Barbara, came to Chris Reddy’s lab at Woods Hole Oceanographic Institution to analyze the samples collected off Santa Barbara.
Chemical “biomarkers” in the oil samples confirmed that the oil in the
sediments originated from natural oil seeps on the seafloor.
(Photo by Alison Olcott, Woods Hole Oceanographic Institution) |
10. Gas chromatograms of oil sampled off Santa Barbara revealed individual compounds in the oil (the red peaks). Chromatograms from the surface slick oil (top) and the seafloor sediments (middle) show nearly an exact match of compounds, confirming that the oil in the sediments comes from natural oil seeps. The bottom chromatogram is of oil from the Exxon Valdez spill. It is clearly identifiable because it does not contain a compound called bisnorhopane (BNH).
(Chromatograms by Bob Nelson, Woods Hole Oceanographic Institution) |