COMPARISON OF THE ORGANIC MATRIX OF FOSSIL AND RECENT BIVALVE SHELLS

Solid-state C-13 nuclear magnetic resonance (NMR) spectra were obtaine d from the insoluble phase of the organic matrices of fossil bivalves from Pleistocene raised beaches on Baffin Island, Champlain Sea locali ties in eastern Ontario, and modern representatives of the same specie s from Nova Scotia and Baffin Island. All the spectra show the presenc e of varying amounts of protein and chitin. The Arctic modern and foss il matrix samples were very well preserved, while the temperate ones s howed breakdown of the chitin. Loss of chitin was verified by high-per formance liquid chromatography (HPLC) analyses, which showed a reducti on in glucosamine and differential loss of amino acids in fossil as co mpared with modern shells of Mya truncata.