GEOCHEMISTRY OF FOSSIL FUEL 



HYDROCARBONS IN MARINE SEDIMENTS: 



SELECTED ASPECTS 



John W. Farrington 



Associate Scientist 



Department of Chemistry 



Woods Hole Oceanographic Institution 



Woods Hole, Massachusetts 02543 



ABSTRACT 



Three investigations are described which illustrate recent advances in 

 analytical chemical and geochemical research on fossil fuel hydrocarbons in the 

 marine environment. 



First: The application of quantitative gas chromatography-mass 

 fragmentography to measure selected aromatic hydrocarbons in marsh and 

 coastal sediments. Instrument precisions of 2 to 3% for 50 x 10' g of 

 naphthalene and 1-methylnaphthalene are achieved. The detection limit for 

 naphthalene (signal/noise ratio of 2:1) is estimated to be 5 x 10' g/g dry 

 weight of sediment with 25-50 g dry weight silt-clay coastal sediments. Using 

 this method No. 2 fuel oil aromatic hydrocarbons incorporated into marsh 

 sediments were precisely measured in samples taken within one week of a spill, 

 and eight months after a spill. 



Second: Several sections from a core in Buzzards Bay, Massachusetts have 

 been analyzed for alkanes, cycloalkanes, and aromatic hydrocarbons. This is an 

 initial attempt at investigating an historical record of anthropogenic fossil fuel 

 inputs to coastal sediments. The results indicate an increase of an order of 

 magnitude in concentrations of fossil fuel hydrocarbons from circa 1810 to 

 1840 to the present. The aromatic hydrocarbon distributions indicate urban air 

 hydrocarbons as the major source. 



Third: The input of fossil fuel hydrocarbons from sewage sludge and dredge 

 spoils in the New York Bight is discussed. An estimated 3.6 x 10 tons of fossil 

 fuel hydrocarbons are discharged each year by dumping in this area. 



INTRODUCTION 



Research concerned with chemical pollutants in the environment can be 

 most easily divided into two broad areas of investigation: biological effects and 



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