The paper presents the first comprehensive geochemical data, obtained by modern techniques, on the dispersed organic matter (OM) of Cambrian sediments in the Upper Proterozoic-Paleozoic Cis-Yenisei sedimentary basin (parametric wells Vostok-1 and Vostok-3). The carbonaceous rocks of the Churbiga and Paidugina Formations are the most OM-enriched in the studied Cambrian sections. The OM in these sections is of aquagene (bacterial, plankton-derived) origin. A detailed description of biomarker hydrocarbons has been given for the fraction of saturated hydrocarbons. Also, the high degree of OM catagenesis (apocatagenesis) has been established. Finally, geochemical criteria for predicting the petroleum potential have been considered.
