Analysis of Trace Metals in Bottom Sediments in Support of Deepwater Biological Processes Studies on the U.S. Mid-Atlantic Continental Slope and Rise. Final Report March 1, 1984 - March 31, 1987

摘要

The concentration of 12 metals (Al, Ba, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, V, and Zn) were measured in sediments over a two year period in order to evaluate the impact of drilling mud discharges on the continental slope off the Middle Atlantic states. Barium, a major element in drilling mud, was the only element found to increase in concentration as a result of drilling and only at stations adjacent to drilling rigs. The small changes (32% or less) were measured only in some of the replicate samples, indicating a patchy distribution of the Ba introduced by drilling. There was no evidence of accumulating drill cuttings in the sediment cores that the authors analyzed. Discrete particles of barite were observed in trap samples and in bottom sediments by means of a scanning electron microscope. The overall goal is to evaluate potential adverse effects of drilling effluents on bottom-dwelling organisms.