Georges Bank Monitoring Program: Analysis of Hydrocarbons in Bottom Sediments and Analysis of Hydrocarbons and Trace Metals in Benthic Fauna during the Second Year of Monitoring

摘要

This program was conducted for the Minerals Management Service (MMS) to document background hydrocarbon and trace metal levels in selected sediments and benthic fauna, and to monitor potential short- and long-term changes resulting from exploratory drilling activities in the Georges Bank Lease Sale 42 region. Aromatic hydrocarbons, as measured by UV/Fluorescence, were present in low (100 ng/g dry weight) concentrations in sediments immediately around the drill rig. Approximately two months after drilling began, an apparent increase in sediment aromatic hydrocarbons occurred immediately around the rig; concentrations approaching 400 ng/g dry weight were observed 5-6 months after the onset of drilling, and remained fairly constant for up to 11 months after the drilling was discontinued. There was no evidence of drilling fluid-related hydrocarbon accumulation in the epifaunal tissues analyzed. Trace metal concentrations in two species Arctica islandica and Paralichthys oblongus were uniformly low for all elements, including Ba.