Petroleum Sources in the Western Gulf of Alaska/Shelikoff Strait Area

摘要

Petroleum hydrocarbons form an important part of the hydrocarbon baseline of the western Gulf of Alaska/ Shelikoff Strait region. The sources that contribute to this baseline include terrestrial and marine natural oil seeps, oil production-related discharges, oil spills from vessels and petroleum product releases from various commercial activities. The purpose of this paper is to define some of the natural petroleum sources present in an area of Alaska that is also part of the spill zone of the Exxon Valdez oil spill (EVOS) and to compare these sources with hydrocarbons in sediment samples from the region. The major impacts of the EVOS occurred within Prince William Sound (e.g. Maki, 1991; Wolfe et al., 1994; Wells et al, 1995). However, after 7 days, EVOS oil was transported out of Prince William Sound into the western Gulf of Alaska region. Any EVOS oil entering the Gulf of Alaska region had been at sea for at least 7 days and generally much longer and had lost, through weathering, a major portion of its toxic fraction (Gilfillan et al., 1995). Because the initial impact was most severe within Prince William Sound, most of the scientific effort was devoted to studies in that region (e.g. Wells et al., 1995; Rice et al., 1996).