Lower Cretaceous organic carbon contents and palynofacies of the Silesian unit

Geoscience Research Reports 39, 2006 (GRR for 2005), pages 45–48

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Abstract

Monotonous, grey to dark grey, prevailingly politic Lower Cretaceous deposits of the Silesian Unit are commonly considered to be deposits of a disoxic to anoxic environment. To find a degree of anoxia of the marine environment the dark grey pelites were sampled for the determination of the content of organic carbon (Corg) and palynological analyses. The contents of organic carbon increase in three intervals; Upper Valanginian (5,76 % Corg), Upper Aptian (3,7 % Corg) and uppermost Albian (2,94 % Corg). The periods of increased anoxia correspond to the oceanic anoxic events designated as OAE lb (Upper Aptian) and OAE ld (Upper Albian).