V.A. Kashirtsev
B.L. Nikitenko
E.B. Peshchevitskaya
E.A. Fursenko

: Russian Geology and Geophysics

A detailed analysis of organic matter from the Oxfordian-Lower Valanginian interval of the Nordvik section (Anabar Bay) allows the definition of three geochemical horizons (terpane, diasterene, and hopane), which are characterized by specific geochemical compounds and their ratios. These horizons are correlated with several stages in the evolution of microfossils associated with ecological and geochemical changes in sea paleobasin. Our study shows a good correlation among the variation in many geochemical parameters, the composition of microfossil assemblages, and the transgressive-regressive phases of the paleobasin evolution. Moderately shallow-water facies was reconstructed using micropaleontological, palynological, and lithological data from the upper and lower parts of the section, where the terpane and hopane horizons were identified.