Cimentação Hidrotermal Em Depósitos Sedimentares Paleogênicos Do Rift Continental Do Sudeste Do Brasil: Mineralogia E Relações Tectônicas

Biochronological Relationships of the Earliest South American Paleogene Mammalian Faunas

“…This leaves the possibility that the Itaboraian SALMA may be not Paleocene but actually early Eocene in age. In addition, based on the events of hydrothermal cementation in the Continental Rift of southeastern Brazil, Sant’Anna and Riccomini (2001) conclude that the main phase of these events at the Itaboraí Basin must have occurred around 50 Ma. An ankaramitic dike that partially cuts the carbonaceous levels of Itaboraí was dated by 40 K– 40 Ar methods in 52.6 ± 2.4 Ma (Riccomini and Rodrigues‐Francisco 1992).…”

Fossil calibration dates for molecular phylogenetic analysis of snakes 1: Serpentes, Alethinophidia, Boidae, Pythonidae

“…Corallus priscus was recovered from fissure fills in travertine deposits at the locality of São José de Itaboraí in Rio de Janeiro, Brazil. The travertine layers are unconformably overlain by a basalt flow dated at 52.6 ± 2.4 Ma (Riccomini and Rodrigues-Francisco, 1992; Gomes Sant'Anna and Riccomini, 2001;Woodburne et al, 2014), which provides a hard minimum age for the taxon. The soft maximum age is the same as for Titanoboa.…”

Brittle reactivation of mylonitic fabric and the origin of the Cenozoic Rio Santana Graben, southeastern Brazil

“…This hypothesis was suggested by the proximity of fault rocks to alkaline intrusions and by mineralizations of barite and fluorite in fractures (e.g., Becker et al, 1997;Valente, 1997). The origin of the process, however, is still uncertain (Ferrari, 2001;Sant'Anna and Riccomini, 2001). The age of the silicification and brecciation processes have been related to the age of fluorite mineralization in the Tinguá intrusion, which yielded a K-Ar age of 50.7 ± 1.2 Ma (Santos, 1994).…”