scholarly journals Dinoflagellate cysts from the Upper Cretaceous (upper Campanian to lowermost Maastrichtian) of the Middle Vistula River section, Poland

Palynology ◽  
2021 ◽  
pp. 1945700
Author(s):  
Mariusz Niechwedowicz
Keyword(s):  
Upper Cretaceous ◽  
River Section ◽  
Dinoflagellate Cysts ◽  
Vistula River ◽  
Upper Campanian

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

2012 ◽  
Vol 62 (4) ◽  
pp. 561-580 ◽  
Author(s):  
Ewa Świerczewska-Gładysz
Keyword(s):  
Sea Level ◽  
Environmental Changes ◽  
River Valley ◽  
River Section ◽  
Sea Level Changes ◽  
Central Poland ◽  
Vistula River ◽  
Hexactinellid Sponge ◽  
Hexactinellid Sponges ◽  
Upper Campanian

ABSTRACTŚwierczewska-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

Stratigraphically important ammonites from the Campanian–Maastrichtian boundary interval of the Middle Vistula River section, central Poland

2012 ◽  
Vol 62 (1) ◽  
pp. 91-116 ◽  
Author(s):  
Marcin Machalski
Keyword(s):  
Formal Definition ◽  
River Section ◽  
Central Poland ◽  
Vistula River ◽  
First Occurrence ◽  
Stratotype Section ◽  
Definition Of ◽  
Boreal Realm ◽  
Upper Campanian

ABSTRACT Machalski, M. 2012. Stratigraphically important ammonites from the Campanian-Maastrichtian boundary interval of the Middle Vistula River section, central Poland. Acta Geologica Polonica, 62 (1), 91-116. Warszawa. The formal definition of the Global Stratotype Section and Point (GSSP) for the base of the Maastrichtian Stage at Tercis, southwest France, is based on the first or last occurrences of twelve taxa, including three species of ammonites, Pachydiscus (Pachydiscus) neubergicus, Diplomoceras cylindraceum, and Nostoceras (Nostoceras ) hyatti. The taxonomy and stratigraphical distribution of these, and allied forms, are studied, on the basis of material from the opoka succession across the upper Campanian-lowermost Maastrichtian boundary in the Middle Vistula River section, central Poland. In view of the imprecise location of two ammonite GSSP markers in that section, a direct ammonite-based correlation with the GSSP at Tercis is impossible. However, data available indicate that in the Middle Vistula River section the first occurrence of Pachydiscus (P.) neubergicus and the last occurrence of Nostoceras (N.) hyatti are situated significantly higher than the first occurrence of Belemnellalanceolata, the traditional belemnite marker for the base of the Maastrichtian Stage in the Boreal Realm, and that Diplomoceras cylindraceum appears significantly below this level. There are no unequivocal records of Pachydiscus (P.) neubergicus from the Belemnella lanceolata Zone s.l. in the Middle Vistula River section.

Planktonic foraminifera and dinoflagellate cysts from the Upper Cretaceous Abderaz Formation in the Koppeh-Dagh Basin, NE Iran

Stratigraphy ◽  
2018 ◽  
Vol 15 (1) ◽  
pp. 47-66
Author(s):  
Elham Davtalab ◽  
Mohammad Vahidinia ◽  
Ebrahim Ghasemi-Nejad ◽  
Alireza Ashouri
Keyword(s):  
Upper Cretaceous ◽  
Planktonic Foraminifera ◽  
Dinoflagellate Cysts ◽  
Ne Iran

Quantitative diagenetic analyses of Edmontosaurus regalis (Dinosauria: Hadrosauridae) postcranial elements from the Danek Bonebed, Upper Cretaceous Horseshoe Canyon Formation, Edmonton, Alberta, Canada: implications for allometric studies of fossil organisms

2014 ◽  
Vol 51 (11) ◽  
pp. 1007-1016 ◽  
Author(s):  
Mackenzie Baert ◽  
Michael E. Burns ◽  
Philip J. Currie
Keyword(s):  
Cross Section ◽  
Upper Cretaceous ◽  
Strong Relationship ◽  
Major Axis ◽  
Minor Axis ◽  
Morphological Features ◽  
Fossil Assemblages ◽  
Fossil Vertebrate ◽  
Horseshoe Canyon Formation ◽  
Upper Campanian

For fossil assemblages, quantitative size and shape studies are often complicated by diagenetic distortion. Different vertebrate elements, although subjected to similar burial stresses, exhibit deformations based upon their original shapes; this hypothesis is tested here by quantitatively comparing deformed humeri and femora from the Danek Bonebed (a monodominant Edmontosaurus regalis bonebed from the upper Campanian Horseshoe Canyon Formation in Edmonton, Alberta, Canada) with samples of undeformed humeri and femora from modern and fossil assemblages. Analyses suggest that at the Danek Bonebed a strong relationship exists between element length and circumference despite being distorted by crushing deformation. Major and minor axes of the midshaft cross section, however, were not uniformly distorted. Although their anatomical position did not change, the major axis became longer relative to the minor axis in distorted specimens. A regression based on the undeformed humeri was not able to accurately predict circumference in the Danek humeri. Further study might quantify the deformation of other bones in the Danek Bonebed and could be extended to other assemblages and genera. Caution should be taken when conducting studies in which diagenetic crushing may have altered morphological features of fossil vertebrate remains.

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