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EN
The biostratigraphic importance, current zonations, and potential for the recognition of the standard chronostratigraphic boundaries of five palaeontological groups (benthic foraminifers, ammonites, belemnites, inoceramid bivalves and echinoids), critical for the stratigraphy of the Santonian through Maastrichtian (Upper Cretaceous) of extra-Carpathian Poland, are presented and discussed. The summary is based on recent studies in selected sections of southern Poland (Nida Synclinorium; Puławy Trough including the Middle Vistula River composite section; and Mielnik and Kornica sections of south-eastern Mazury-Podlasie Homocline) and of western Ukraine (Dubivtsi). The new zonation based on benthic forams is presented for the entire interval studied. Zonations for ammonites, belemnites and inoceramid bivalves are compiled. All stage boundaries, as currently defined or understood, may easily be constrained or precisely located with the groups discussed: the base of the Santonian with the First Occurrence (FO) of the inoceramid Cladoceramus undulatoplicatus; the base of the Campanian with the Last Occurrence (LO) of the crinoid Marsupites testudinarius and approximated by the range of the foraminifer Stensioeina pommerana; and the base of the Maastrichtian approximated by the FO of the inoceramid bivalve Endocostea typica and the FO of the belemnite Belemnella vistulensis. The positions of substage boundaries, as currently understood, are constrained in terms of the groups discussed.
EN
The Upper Campanian–Lower Maastrichtian interval of the Middle Vistula River Valley section records the following benthic foraminiferal bioevents in ascending stratigraphical order: LO of Globorotalites michelinianus, FO and LO of Globorotalites emdyensis (=G. hiltermanni), FO of Bolivina incrassata, FO of Bolivinoides miliaris, FO of Angulogavelinella gracilis (=A. bettenstaedti), LO of Gavelinella monterelensis, FO of Osangularia navarroana, FO of Bolivina decurrens and FO of Neoflabellina reticulata. These events are recorded in very similar stratigraphic positions in the Lägerdorf-Kronsmoor succession (northern Germany) and in the succession of eastern England and, at least some of them, in eastern Europe. Accordingly they can serve as important markers for stratigraphic correlation across Europe. The FOs of the planktonic species, Rugoglobigerina milamensis, R. hexacamerata and R. pennyi, in the uppermost part of the “Inoceramus” redbirdensis Zone,are very close to the Campanian–Maastrichtian boundary as defined by inoceramid bivalves (Walaszczyk, 2004) and we propose these planktonic foraminiferal bioevents as a good proxy for this boundary in temperate regions.
EN
The stratigraphical distribution of Porosphaera globularis, a common calcareous sponge in the Upper Cretaceous (mostly Campanian and Maastrichtian) of Poland was studied. The presented material, both new and from museum collections, comes from the Campanian of the Miechów Synclinorium, in southern Poland, and from the Lower Campanian of Mielnik in the south-eastern part of the Mazury-Podlasie Homocline, in eastern Poland. The significance of the species in extra-regional correlation, its palaeobiogeography and stratigraphical potential is critically reviewed.
EN
A combined micropalaeontological and stable isotope study of the Dubivtsi chalk in the Western Ukraine indicates its middle late Turonian age. One long-term and clearly distinguishable positive excursion of the isotope curve (d1318
EN
A 40-m-thick section of chalk exposed in the Chełm quarry (SE Poland) contains a rather poor assemblage of macrofauna and a well diversified assemblage of foraminifers. The planktonic foraminifer assem- blages characterized by a considerable number of representatives of Globigerinelloides and Heterohelix and the presence of Guembelitria cretacea indicate the lowest part of the Guembelitria cretacea Zone sensu Peryt (1980). Benthic foraminifers point out that the strata of the Chełm quarry section can be attributed to the lower part of the Upper Maastrichtian: i.e., the Gavelinella danica/Brotzenella preacuta Zone of the European Boreal Province or the Anomalinoides pinguis Zone distinguished in Poland (except the Carpathians). The occurrence of ammonites, such as Hoploscaphites constrictus lviviensis Machalski, Hoploscaphites schmidi (Birkelund), and Acanthoscaphites varians blaszkiewiczi Jagt & al. indicates that the Chełm succession belongs to the lower part of the Belemnitella junior Zone, i.e., to the Belemnitella junior–Spyridoceramus tegulatus Zone sensu Schulz & Schmid (1983). The correlation of the Chełm quarry section and the Middle Vistula River Valley section indicates that the equivalent interval of the former section is not exposed in the Middle Vistula River Valley and that it would occur between the Chotcza and Lucimia villages within the lower part of the Belemnitella junior Zone, i.e., within the Belemnitella junior-Spyridoceramus tegulatus Zone distinguished in NW Germany (Schulz & Schmid,1983).
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