Calcareous nannoplankton from the Korytnica basin (Middle -Miocene; Holy Cross Mountains, Poland)

Abstract

Calcareous nannoplankton from the Korytnica basin, Holy Cross Mountains, Central Poland, indicate the presence of standard nannoplankton zones NN 5 (Sphenolithus heteromorphus Zone) and NN 6 (Discoaster exilis Zone) in the Lower Opolian Formation. Species present and correlations to the Central Paratethys, the Mediterranean area, and the North Sea Basin are discussed. They indicate that the Korytnica Clays are equivalent to the upper part of the type Langhian, and they cannot be correlated with the type Tortonian.