title: Historical changes in trace metals and hydrocarbons in nearshore sediments, Alaskan Beaufort Sea, prior and subsequent to petroleum-related industrial development: part II. Hydrocarbons.
abstract: Composition and concentration of hydrocarbons (normal and isoprenoid alkanes, triterpenoids, steranes, and PAHs) in nearshore surface sediments from Elson Lagoon (EL), Colville Delta-Prudhoe Bay (CDPB) and Beaufort Lagoon (BL), Alaskan Beaufort Sea, were assessed for spatio-temporal variability. Principal component analysis of the molecules/biomarkers concentrations delineated CDPB and BL samples into two groups, and cluster analysis identified three station groups in CDPB. Overall there was no geographic distribution pattern in the groups. The diversities between groups and individual samples are attributed to differences in n-alkanes and PAHs contents, which are influenced predominantly by sediment granulometry and sitespecific fluvial input. The predominant hydrocarbon source is biogenic, mainly terrigenous, with hardly any contribution from natural oil seeps, oil drill effluents and/or refined crude. The terrigenous source is corroborated by δ(13)C, δ(15)N, and OC/N of sediment organic matter. Time interval (1976-1977, 1984 and 1997) changes in hydrocarbon compositions and concentrations in CDPB are not significant.
authors.affiliation: Institute of Geophysics and Planetary Physics, University of California at Los Angeles, 5863 Slichter Hall, Los Angeles, CA 90095, USA. Electronic address: indira@ucla.edu.
authors.forename: M Indira
authors.initials: MI
authors.lastname: Venkatesan
authors.forename: A Sathy
authors.initials: AS
authors.lastname: Naidu
authors.forename: Arny L
authors.initials: AL
authors.lastname: Blanchard
authors.forename: Debasmita
authors.initials: D
authors.lastname: Misra
authors.forename: John J
authors.initials: JJ
authors.lastname: Kelley
mesh_terms: D000413:Alaska; D004784:Environmental Monitoring; D019652:Extraction and Processing Industry; D019015:Geologic Sediments / Q000737:chemistry*; D008670:Metals / Q000032:analysis*; D059392:Petroleum Pollution / Q000706:statistics & numerical data; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D012623:Seawater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014877:Water Pollution, Chemical / Q000706:statistics & numerical data
chemical_list: D008670:Metals; D011084:Polycyclic Aromatic Hydrocarbons; D014874:Water Pollutants, Chemical
keywords: Alaska; Beaufort Sea; Contaminants; Sediment hydrocarbons