Download PDF

IDENTIFICATION OF THE GENETIC TYPE AND THERMAL MATURITY OF ORGANIC MATTER IN SEDIMENTARY ROCKS BASED ON THE STUDY OF KEROGENS FROM WESTERN SIBERIA AND ADJACENT AREAS

L. S. Borisova, I. D. Timoshina, A. N. Fomin, A. P. Rodchenko

Trofimuk Institute of Petroleum Geology and Geophysics SB RAS, Novosibirsk, Russia

Results of the study of composition and elemental geochemistry of kerogens using IR spectroscopy, elemental analysis, and Rock-Eval pyrolysis are presented. Materials of kerogens were extracted from coals and bituminous shale from the Kuznetsk basin (Kuzbass), as well as from other sedimentary rocks (characterized by varying genetic origin and thermal maturity of organic matter) from Western Siberia and adjoining areas of the Yenisei-Khatanga regional trough.The structural parameters of kerogen (IR spectra) which were used to characterize the type and degree of catagenetic transformation of the organic matter, similarly describe the elemental composition in the van Krevelen diagram. The combination of pyrolysis, IR spectroscopy, and elemental analysis is shown to be an effective method for characterization of source rocks and their affiliation with the main oil generation zone (oil window) and deep gas generation zone (gas window). Correlations between the parameters of different methods for the study of kerogen have been revealed.

Keywords: kerogen, elemental composition, IR spectroscopy, pyrolysis, Jurassic-Cretaceous deposits, brown coals and bituminous shale, Western Siberia and adjacent territories.

DOI 10.20403/2078-0575-2025-4a-3-12

​ ​​​​​​​​​​​