Home – Home – Jornals – Russian Geology and Geophysics 2018 number Неопубликованное

The degree of the organic matter (OM) maturation in Proterozoic, Paleozoic, and Mesozoic deposits in the Anabar-Khatanga saddle is determined from examination of reflectance characteristics of macerals (mainly vitrinite). Deposits of the Proterozoic are marked only by the presence of graphite inclusions of uncertain origin. In Cambrian, Devonian, and Carboniferous strata, the organic matter is transformed predominantly to apocatagenesis grades (АC_2-3). Approximately similarly altered OM (АC_1-3) is reported from the Tus-Takh Formation and Lower Kozhevnikova Formations (Lower Permian). In individual wells and areas, the degree of OM transformation is shown to be not higher than МC₁²-МC₂ grades of mesocatagenesis (classification after A.E. Kontorovich). In the Upper Kozhevnikova Formation, catagenesis grades range within МC₁¹-АC₁ for the Upper Permian, and within МC₁¹-МC₃² for the Triassic. In Jurassic deposits, the organic matter has generally reached early mesocatagenesis (МC₁¹-МC₁² grades), and МC₂ grade in the deepest buried areas. In Cretaceous strata, the OM has been altered to a lesser extent, corresponding to PC₃-МC₁¹, rarely to higher, grades of catagenesis. Prospects of petroleum generation may be associated with individual Permian, Triassic and Jurassic-Cretaceous sequences showing moderate level of the organic matter maturity.