Hexactinellid sponge assemblages across the Campanian– Maastrichtian boundary in the Middle Vistula River section, central Poland

Abstract

Świerczewska-Gładysz, E. 2012. Hexactinellid sponge assemblages across the Campanian-Maastrichtian boundary in the Middle Vistula River section, central Poland. Acta Geologica Polonica, 62 (4), 561-580. Warszawa.The sponge fauna from the Upper Campanian-lowermost Maastrichtian succession of the Middle Vistula River valley (central Poland) is represented mainly by dictyid hexactinellid sponges (Hexactinosida and Lychniscosida). Their greatest abundance and taxonomic variability is noted in the "Inoceramus" inkermanensis Zone (Upper Campanian), and they are less diverse in the overlying (Upper Campanian) Trochoceramus costaecus Zone and lower "Inoceramus" redbirdensis Zone. In the upper "Inoceramus" redbirdensis Zone (basal Maastrichtian in the sense of the Tercis rather than the Boreal definition) they are extremely rare. With the beginning of the Maastrichtian the number of dictyid sponges gradually increases.The observed changes in the abundance and taxonomic variability of the dictyid sponges indicate environmental changes in the latest Campanian-earliest Maastrichtian sea in the area. It seems that changes in basin bathymetry, confined to eustatic sea-level changes in the latest Campanian and early Maastrichtian, were the most important factor. Progressive shallowing of the basin in the latest Campanian drastically restricted the development of dictyids. In the peak regression, the sea level could have fallen to only several tens of metres. The gradual recovery of the sponge assemblages correlates with subsequent deepening of the basin with the start of the Maastrichtian.

BOLIVINOIDES(BENTHIC FORAMINIFERA) FROM THE UPPER CRETACEOUS OF POLAND AND WESTERN UKRAINE: TAXONOMY, EVOLUTIONARY CHANGES AND STRATIGRAPHIC SIGNIFICANCE

“…On the British Isles, the last appearance of the species was recorded in the lower part of the Belemnella lanceolata Zone (Barr, 1966). The slightly lower position of the disappearance of B. decoratus recorded in Poland compared to western Europe could be a result of infrequent occurrences in the uppermost Campanian of Poland, which corresponded to a significant regression observed in the area (Dubicka & Peryt, 2012a;Świerczewska-Gładysz, 2012). In other places around the world, the last appearances of B. decoratus were roughly similar to those recorded in western Europe (uppermost Campanian), for example, Trinidad , Libya (Barr, 1970) and the Atlantic Coastal Plain of North America (Petters, 1977).…”

Integrated biostratigraphy of the Santonian through Maastrichtian (Upper Cretaceous) of extra-Carpathian Poland

“…The recent studies on the succession add much to the general knowledge of this interval (Remin 2012(Remin , 2015Machalski 2012;Keutgen et al 2012;Świerczewska-Gładysz 2012;Peryt and Dubicka 2015;Plasota et al 2015). It is also easily accessible in the Nida Synclinorium (Jurkowska 2016).…”

Magnetostratigraphy of the Campanian/Maastrichtian boundary succession from the Middle Vistula River section, central Poland

“…2): ammonites (B³aszkiewicz, 1980;Machalski, 1996Machalski, , 2012Remin et al, 2015), bel em nites (Kongiel, 1962;Remin, 2012Remin, , 2015Keutgen et al, 2012), inoceramids (Walaszczyk, 2004), foraminifers (Po¿aryska, 1954, Po¿aryska andPeryt, 1979;Peryt, 1980Peryt, , 2000Peryt and Dubicka, 2015), and nannofossils (GaŸdzicka, 1978;Bur nett et al, 1992). Also groups with lit tle or poorly known biostratigraphic po ten tial, but rep re sent ing dom i nant el e ments of the re cord, were in ten sively stud ied; gas tro pod and bi valve molluscs (Abdel-Gawad, 1986) or sponges (OEwierczewska-G³adysz, 2006(OEwierczewska-G³adysz, , 2012. Kongiel (1962) raised the base of the Maastrichtian into the mid dle part of Po¿aryski's unit t, cor re spond ing to the low est oc cur rence (FO) of the bel em nite Belemnella (Belemnitella ac cord ing to that au thor) lanceolata (Schlotheim), in agree ment with the place ment of the bound ary at that time, as widely used in Bo real and West ern Eu rope (Arkhangelsky, 1912;Jeletzky, 1951; see also Birkelund et al, 1984).…”