When most people think of Louisiana as being unique, they think of Mardi Gras, crawfish and Cajun culture. Few realize that what lies beneath the Gulf of Mexico along Louisiana's coast is also unique, from the terrain and habitat to the animals living there. And two LSU scientists are diving down some 3,000 meters to explore it.

Scientists Harry Roberts and Bob Carney are combing the most unique continental slope in the world to study some of the most unique animal communities on the planet - all just off the coast of Louisiana.

Roberts and Carney are studying 14 different sites where oil and gas seep up from the bottom of the Gulf. In particular, they are studying the animals that live near these "seeps." These organisms include bacteria that feed on hydrogen sulfide gas, a by-product of the oil and gas seepage; tube worms, mussels and clams that serve as hosts to those bacteria; and shrimp, crabs, fish, snails and starfish that, in turn, feed on the worms, mussels and clams. These animal communities are unique because they only exist near these seeps, and because the bacteria at the base of the food chain are "chemosynthetic," or grow without sunlight.

The large number of oil and gas seeps and the vast amount of salt under the Gulf floor near Louisiana's coast, along with all the sediment dumped into the Gulf by the Mississippi River, make the continental slope off the coast of Louisiana unique. "It's the most complicated continental slope in the world, geologically," Roberts said. "There are more seep communities off the coast of Louisiana than most places in the world. The salt, the oil and gas and the sediment create a very dynamic geologic framework".



Posted by: Kelly    Source