The Formation of Fossil Organic Matter and its Bulk Composition

4 The Formation of Fossil Organic Matter and its Bulk Composition 

Fulvic acids and subsequently humic acids decrease in their concentrations over time as a result of progressive combination reactions with increasing diagenesis. This process of kerogen formation concurrently involves the elimination of small molecules like water, carbon dioxide, ammonia or hydrogen sulfide (Hue and Dmand 1977). As a consequence, the degree of condensation of the macromolecular kerogen increases. In terms of elemental composition it becomes 

A small portion of sedimentary organic matter is soluble in organic solvents and contains lipid compounds that are either directly inherited from the biological precursor organisms or cleaved by hydrolysis from larger cellular units like cell walls or membranes (cf Figs. 4.9 and 4.10). The compounds inclnde individual 

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