Utwory trzeciorzędowe z otworu Szczecin IG I w świetle badań mikropaleontologicznych

Abstract

TERTIARY FORMATIONS FROM BORE HOLE SZCZECIN IG I IN THE LIGHT OF MICROPALAEONTOLOGICAL EXAMINATIONSSummaryThe present paper deals with the results of micropalaeontological examinations of the Tertiary formations pierced by the bore hole Szczecin IG-I in the Polish Lowland area. On microfaunistic analysis, the author has distinguished here the Miocene deposits (depth 50,50÷126,00m), Middle Oligocene (Rupelian) deposits (depth 126,00÷127,00 m), and Upper Eocene deposits (depth 190,00÷281,00 m) that rest under the Quaternary strata. Tertiary formations resting below 281 m are examined from the palaeobotanical point of view only, since the coal-bearing deposits representing these formations do not contain microfauna. TheEocene formations pierced by the bore hole here considered, are characterized by not too rich foraminifer fauna represented by Hastigerina micra (Cole), Cibicides westi (Howe), Cibicides carinatus (Terq.) emend. le Calve’z, Trifarina wilcoxensis (Cush. Et Pont.) and others, and by very abundant radiolarians. The richest foraminifers are Rupelian deposits containing such index species as Turrilina alsatica (Andreae), Rotaliatina bulimoides (Reuss), Alabamina tangentialis (Clod.), Alabamina perlata (Andreae) and others. The Miocene deposits resting higher up are characterized by poor foraminifer microfauna. Here are found only few representatives of Uvigerina asperula Czjzek, Globigerina bulloides d’Orb., Stilostomella longiscata (d’Orb.) and others, and fairly abundant diatoms (Coscinodiscus sp.). Since the richest foraminifer material has been supplied by the Rupelian formations, the present author compares the Rupelian microfauna from Szczecin with that from certain bore holes made in West Poland, previously described by H. Wolańska (1964), and with the Rupelian microfauna cited by German authors (C. Ellerman, 1958; J. Indans, 1958; D. Spiegler, 1960; Y. Kiesel, 1962; Table 1). Table 2 shows the age extent of the more important foraminifers that occur in the Rupelian pierced by the bore hole Szczecin IG I.