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Geology & Geochemistry of Combustible Minerals No. 3-4 (176-177) 2018, 49-62.

Yuri KHOKHA, Oleksandr LYUBCHAK, Myroslava YAKOVENKO

Institute of Geology and Geochemistry of Combustible Minerals of National Academy of Sciences of Ukraine, Lviv, e-mail:


Experiments on artificial “maturation” of humic acids, kerogen, model compounds of organic compounds and individual hydrocarbons up to 4000 hours carried out in a wide range of pressures and temperatures were considered. An analysis of trends in the change in the composition of gases over time, which was formed during experiments, was carried out. It is concluded that in the considered experiments the state of thermodynamic equilibrium is not achieved; they only show tendencies in the changes of the solid, liquid and gas phase. A method for simulating artificial maturation of organic compounds in the process of catagenesis, based on the Jaynes formalism, was developed. An equilibrium concentration of gases in contact with a humic substance depending on temperature is calculated. The results of the calculation are in good correspondence with the trends shown by experimental studies.


gas-generation, humic acids, catagenesis, Jaynes formalism, equilibrium thermodynamics.


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