The Geochemical Associations of Metals and Organic
THE GEOCHEMICAL ASSOCIATIONS OF METALS AND ORGANIC MATTER IN WEST COAST SCOTTISH SEDIMENTS. by DAVID ODONNELL B.Sc. A Thesis Submitted For The Degree Of DOCTOR OF PHILOSOPHY At The University Of Edinburgh. December 1987. To My Father Terry O'Donnell Science, beauty, freedom, adventure, what more could you ask for in life?" Charles A Lindberg ABSTRACT. Thirteen sediment cores have been collected from a variety of sedimentary environments around the coast of Western Scotland ranging from terrestrially dominated fjords to more marine shelf areas. Eight of these cores have been examined in detail for the minor elements (Cu, Pb, Zn, Zr, Rb, Sc, Sr, Ba, Ni, Cr, Y), Rare Earth elements (La, Ce, Nd), organic components (C, N, S. I, Br,) and porewater components (S042 , alkalinity). In addition, some cores were analysed for 615N and also 137Cs (to estimate sediment accumulation rates). Study of the minor elements associated with the lithogenic fraction (Zr, Rb, Sc, Sr, Ba, Ni, Cr) has highlighted variations in sediment mineralogy and grain-size both spatially and temporally, showing that few of the sediments show steady state accumulation. Indeed, in one core an erosive event can be identified which has been calculated to have removed 18cm of sediment accumulation. In these sediments Ni and Cr have been shown to be associated with the detrital ferromagnesian fraction. Ni can therefore be used as an indicator of Iithogenic metal input. The distibution of the REE (La, Ce, Nd) show enrichments of La and Ce relative to V and mean shales in the more terrestrially dominated fjords suggesting a possible association with the iron oxide phase.
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