Marine organic geochemistry of the Eastern Mediterranean: 1. Aliphatic andpolyaromatic hydrocarbons in Cretan Sea surficial sediments

As part of a lipid biogeochemical study, aliphatic and polyaromatic hydroca rbons were determined in surficial sediments from the Cretan Sea (South Aeg ean Sea) in the Eastern Mediterranean. Total concentrations of both aliphat ic (AHC) and polyaromatic (PAH) hydrocarbons were low (562-5697 and 14.6-15 8.5 ng/g, respectively) with respect to other coastal sediments worldwide a nd compare with concentrations found in open sea areas. The composition of AHC was dominated by unresolved complex mixture (UCM) indicating the presen ce of petroleum-related hydrocarbon inputs as confirmed by the detection of specific alpha,beta-hopanes, PAH consisted mainly of pyrolytic four- to fi ve-ring compounds. UCM and PAH amounts revealed that Cretan Sea receives lo w supply of anthropogenic material compared to NW Mediterranean. The spatia l distributions of AHC and PAH indicated that urban run-off and transport f rom the continental self are the major input pathway of anthropogenic and b iogenic hydrocarbons from terrestrial sources in the near shore area: where as atmospheric transport might be the significant source of hydrocarbons in the deep area. (C) 2000 Elsevier Science B.V, All rights reserved.