Campus News

Oil and water

A UGA researcher who recently returned from the site of the Deepwater Horizon oil rig explosion said at a June 8 press conference that her observations told a consistent story: it’s “unlike anything seen in human history.”

Samantha Joye, a professor of marine sciences in the Franklin College of Arts and Sciences, described preliminary findings from a two-week research expedition aboard the R/V F.G. Walton Smith in the Gulf of Mexico, near the Deepwater Horizon site. Joye returned from the expedition June 6.

The release of oil from Deepwater Horizon is of greater magnitude and scope than any previous spill. It’s also unique, as it has introduced unprecedented quantities of both oil and methane gas into the deep, cold waters of the Gulf of Mexico.

Throughout Joye’s career, her research has focused on naturally occurring gas and oil seeps in the Gulf, commonly called “cold seeps.” Now, however, her research focus shifted to characterizing the effects of hydrocarbons on microbes in the ecosystem following the massive oil spill. Although not readily seen by the public-unlike the oil-soaked fish, birds and marine mammals that have made headlines-the diverse microbial community that thrives in the sediments and deepwater of the Gulf forms the base of the food web.

Researchers in Joye’s lab and other UGA marine scientists’ labs are analyzing data gathered by a National Oceanic and Atmospheric Administration-funded cruise, which first discovered deepwater plumes associated with the oil spill, and data from the just-returned F.G. Walton Smith expedition, supported by a National Science Foundation rapid response award to Joye.

The goals of the cruise were to track the plume as close as possible to the origin of the spill, document the extent of the oil and methane in the water and evaluate oxygen consumption in the plume.

During the press conference, Joye showed three charts with data that showed the dynamics of the plume over space and time. The three charts contrasted a control site, the core of the plume just ¾ mile from the well head and a third site located 8 to 10 miles from the well head.

The researcher’s preliminary data show that methane increased with proximity to the plume and oxygen decreased with distance from the plume as a result of increased microbial activity over time.

Joye said she would not go so far as to predict that the depleted oxygen would result in “dead zones,” low-oxygen areas where marine life cannot be supported.

Some marine scientists have expressed concern that in addition to the impact on the microorganisms at the bottom of the food web-microorganisms-important fisheries, like tuna, would be stressed from lack of oxygen.

Joye said she has been working in the Gulf of Mexico for 15 years. And in that time she has “never seen concentrations of oil and methane this high anywhere.”

“The feature was strongest near the Deepwater Horizon spill site and decreased as you moved away,” she said.

Systems like the Gulf of Mexico are accustomed to slow seeps of oil and gas, according to Joye.

“The Gulf of Mexico ordinarily is in a stable, steady state, but the oil spill has created an imbalance in the system,” she said.

The magnitude of oil and methane from the spill may have overwhelmed the microbial community’s ability to consume the introduced oil and gas, she said.

Joye disputed assertions that the Gulf of Mexico is so large that the oil spill does not matter.

“The solution to pollution is not dilution,” she said. “This is an excuse, arm-waving. It is unacceptable to say it doesn’t matter.

“It will be months, even years, before we know the full consequences of the spill,” she added.