Samples of eolian dust and comparably sized desert surface sediment samples collected over widely scattered regions of northwest Africa were analyzed for carbon, nitrogen, and hydrogen content and total carbohydrate. Infrared analysis and gas chromatographic analysis were also performed on organic components extracted from several of these samples. Although the total carbon content of the eolian dust samples varies from 2.8 to 7.0% by weight, the organic carbon component is relatively uniform at 2.9¿0.5%. By comparison, the average organic carbon content of the African surface sediments is 0.7¿0.5%. Total carbohydrate content averages 0.128% for the dust and 0.022% for the desert sediments. These results, coupled with mineralogical analysis particle size distribution, and chemical reactivity studies, indicate that these desert regions are not presently the principal sources of eolian material transported over the North Atlantic Ocean. |