Hedges (OCE-9711690) ABSTRACT Hedges OCE-9711690 A major area of interest in marine sciences is the distribution and preservation of organic matter in marine sediments. The PI has been a key contributor to studies in this area, and he proposes to continue his research on the forms, distributions and preservation of organic matter in marine sediments. A major aim of this proposal is to identify shifts in the major biochemical compositions of sedimentary organic mixtures subjected to varying extents of degradation. New analytical techniques would be brought to bear on existing sediment samples which would be selectively extracted for organic carbon. Thus in addition to bulk characterizations, analyses by 13C NMR would be added to provide more detailed organic compositional data. Results from this study would be expected to unravel the two fundamental issues in the preservation of organic matter in marine sediments, namely 1) how oxygen-sensitivity relates to protective sorption of organic matter in sediments and 2) to what extent oxygen- sensitive organic matter might be directly derived from hydrolysis-resistant biomacromolecues.
