Temporal and spatial changes in the concentrations of hydrocarbons and trace metals in the vicinity of an offshore oil-production platform

摘要: Abstract A 4-year multidisciplinary monitoring program was conducted between October 1986 and 1990 to detect quantify environmental impacts related oil gas drilling in the Arguello Field southern California. As part of this program, concentrations trace metals petroleum hydrocarbons were determined surface sediments trapped before, during, after had stopped. Barium, a major component muds, only chemical that changed significantly during period study. During drilling, barium increased 30–40% above background. After stopped, decreased but, 1.5 years, not approached background sediments. In sediments, 200–300% but returned within 1 year Hydrocarbon from study area occasionally elevated, generally consistent with activities. Examination hydrocarbon PAH distributions indicated distinct signal observed some samples; however, natural seepage rather than discharges is probably responsible for randomly-elevated concentrations. The presence seep-related particles should be recognized characterizing ambient area. peak periods, neither nor detected are likely impact benthic biota vicinity platform.