Carbon Isotope Composition and Concentration of Fe-Group Elements in the Sedimentary Organic Matter from Rocks of Different Ages

The Fe/Co ratio (ppm) in the kerogen from different-aged clastic sediments (Early Proterozoic-Mesozoic) varies from 17 to 4100, and delta C-13 value varies from -14.8 to -32.6 parts per thousand. The relationship between Fe/Co and delta C-13 is determined by the composition of microbial biota in paleobasins and superimposed metamorphic processes. The kerogen from the Vendian deposits of the East European Platform, containing a large amount of saprophytes and actinomycetes is characterized by the maximum Co concentration. The kerogen from deposits metamorphosed under amphibolite-facies conditions are characterized by the minimal delta C-13 and the maximum Fe/Co ratio values.