EARLY DIAGENESIS AND RECYCLING OF BIOGENIC DEBRIS AT THE SEA-FLOOR, SANTA-MONICA BASIN, CALIFORNIA

While the majority of reactive organic compounds degrade quickly, with a half-life of ≤6.5yr, 1/4 of the total metabolizable organic matter appears to react more slowly, with a half-life on the order of 1700yr. Down-core changes in pore water sulfate and titration alkalinity are not explained by stoichiometric models of organic matter diagenesis and suggest that reactions not considered previously must be influencing the pore water concentrations. Measured recycling and burial rates indicate that 43% of the organic carbon reaching the basin seafloor is permanently buried. It appears that carbon burial rates are primarily controlled by input rates and not by variations in preservation. -from Author