Profil mikrofaunistyczny miocenu w Łękach Dolnych oraz próba jego rozpoziomowania

Abstract

THE MICROPHAUNA OF THE MIOCENE AT ŁĘKI DOLNE (SUBCARPATHIANS) AND ATTEMPT OF ITS STRATIGRAPHICAL DIVISIONThe bore-hole of Łęki Dolne is situated 5 kms. west of Pilzno (Rzeszów Voivodship). Here the Miocene sediments are wedged in between Flysch deposits. The substratum are Krosno beds. The Miocene sediments consist of from the bottom (100-123.3 m.), grey clays of homogeneous silty texture; higher up, yellowish-grey clays with sand intercalations; finally, 60 m. from the top, clays alternately silty and intercalations of arenaceous clays. The microfauna of the Łęki Dolne bore-hole is abundant and variegated. All the species belong to 20 families among which most amply represented are the Lagenidae and Buliminidae families, as well as the Rotaliidae family and some planktonic species; characteristic and important is the appearance of species from the following families: Textulariidae, Valvulinidae, Miliolidae, Camerinidae and Amphisteginidae. In the Łęki Dolne bore-hole the author distinguished 3 microfauna zones; the lower and upper zones show distinctly separate microfauna assemblages, whereas the third zone, situated in the middle, might be called a reduced section of two or three zones, and has therefore been called a "relic zone".