Artículos de revistas
Fin d'un mythe géologique moderne: Il n'y a pas de rudistes au Brésil! et ses implications paléobiogéographiques
Fecha
2015-07-14Registro en:
Carnets de Geologie, v. 15, n. 11, p. 123-136, 2015.
1634-0744
1765-2553
10.4267/2042/56880
2-s2.0-84938925610
Autor
CS 93837
The University of Kansas
Universidade Estadual Paulista (Unesp)
Institución
Resumen
Out of the few records of rudists from the Cretaceous strata of the South Atlantic coastal basins only two refer to Brazilian localities. However, petrographic analyses demonstrate that these shells should be assigned to Ostreids or to Pycnodontids rather than to Rudistids. More specifically, the domain considered herein, north of the Río Grande Rise -Walvis Ridge barrier, was part of the warm-water tropical realm, but it was not part of the Mesogean domain because both Rudistids and Orbitolinas are missing. In addition, the scarcity of corals leads us to ascribe the taphonomic assemblage to the Chloralgal facies. Neither generalized hypersalinity or extreme sea-water tempe-ratures seem to account for these biotic peculiarities. Instead, our alternative hypothesis favors the driving role played by oceanic circulation in the dispersal of the benthic organisms.