Joining this second research cruise, again headed by Fisher, was Helen White, whose expertise as a geochemist was key to the interdisciplinary effort. "It is easy to see the impact of oil on surface waters, coastlines and marine life, but this was the first time we were diving to the seafloor to examine the effects on deep sea ecosystems," says White, who directs the new Tri-College Environmental Studies Program at Haverford College.
To examine the deep water, the team employed the autonomous underwater vehicle Sentry to map and photograph the ocean floor and the deep submergence vehicle Alvin to get a better look at the distressed corals. Alvin holds a pilot and two passengers, and is equipped with viewports and cameras. Alvin also has robotic arms that can manipulate instruments to collect samples. During six dives in Alvin, whose manipulator claws were modified with a cutting blade, the team collected sediments and samples of the corals and filtered the brown material off of the corals for analysis. "Collecting samples from the deep ocean is incredibly challenging, and Alvin is crucial to this kind of work," says White, who got the chance to observe the corals up close onboard the submarine during one of the scheduled dives.
"As a geochemist, my primary aim in this research was to determine the composition of the brown flocculent material covering the corals and the source of any petroleum hydrocarbons present," says White, who brought Catherine Sheline, a Haverford College sophomore chemistry student along with her on the research cruise. Upon returning to Haverford, four other students worked with White in her lab to analyze some of the samples, including chemistry majors Jenine Abbassi and Lindsay Ryan and biology majors Elizabeth Coward and Elizabeth Willis.
Because oil can naturally seep from cracks in the sea floor of the Gulf,
|Contact: Eils Lotozo|
Woods Hole Oceanographic Institution