Opportunistic sampling at a deep-water synthetic drilling fluid discharge site in the Gulf of Mexico

Abstract

From the Abstract: "Two opportunistic benthic surveys werre conducted at an offshore semisubmersible oil drilling rig located in 656 m of water on the continental slope of the Gulf of Mexico to determine the extent of synthetic-based drilling fluid concentrations in surrounding sediments and the composition of the associated macrofauna and megafauna communities...Between July 1997 and March 1998, the densities of polychaetes and gastropods increased sharply in the study area. In March, polychaete density, gastropods density, and Petrolee concentrations were all significantly higher northeast of the drill site compared with southwest. Polychaete and gastropod densities northeast of the drill site were roughly 3,600 and 3,000 times higher than those reported in eastern and western areas of the northern Gulf of Mexico at similar depths, respectively.