engleski

Latest Maastrichtian Rudist association of Apulia (Italy, Croatia, Greece): Implications for the Extinction of the Hippuritoidea

Based on biostratigraphy, a Late Maastrichtian age of rudist limestones of the Adriatic microplate, or Apulia, was reported previously, but according to the present state of knowledge, the latest Maastrichtian rudist associations of the region are rather species-poor. This is supported by Sr-isotope stratigraphy (SIS) for inner platform deposits of the Island of Brac (Croatia). However, SIS indicated a numerical age of c. 66 Ma for the Ciolo Limestone of Salento (southern Italy), and for rudists from megabreccias exposed on the Ionian Islands (Greece). Both types of deposits contain species-rich rudist associations (Pironaea, Hippurites, several genera of Radiolitidae, Mitrocaprina). Large shells of ?Pseudosabinia are particularly abundant. The Ciolo Limestone was deposited at the margin of the Apulian platform and is unconformably followed by Tertiary limestones, while the megabreccias of the Ionian Islands accumulated at the toe-of-slope and are overlain by pelagic mudstones, which contain the K/P boundary. These results indicate that species-rich rudist associations existed in the central Mediterranean Tethys during the latest Maastrichtian. This is important for further evaluations of the pattern and causes of extinction of the group at the end of the Cretaceous.

strontium isotope stratigraphy; Maastrichtian; rudist; Adria; Apulia; extinction

nije evidentirano