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Carbon isotope fluctuations in Precambrian carbonate sequences of several local...
Sial, Alcides N.; Ferreira, Valderez P.; Almeida, Afonso R. de; Romano, Antonio W.; Parente, Clóvis Vaz; Costa, Marcondes L. da; Santos, Victor H.Carbon isotope fluctuations in Precambrian sedimentary carbonates between 2.8 Ga and 0.60 Ga in Brazil are examined in this study. The carbonate facies of the BIF of the 2.8 Ga-old Carajás Formation, state of Pará in northern Brazil, has rather homogeneous delta13C (-5 o/ooPDB), compatible with carbonatization of a silicate protolith by a CO2-rich fluid from mantle degassing. The Paleoproterozoic Gandarela Form...
Cretaceous-Paleogene transition at the Paraíba Basin, Northeastern, Brazil:Carb...
Silva, Maria V. Nascimento; Sial, Alcides N.; Ferreira, Valderez P.; Neumann, Virgínio H.; Barbosa, José A.; Pimentel, Marcio M. PimentelThe Paraíba Basin in northeastern Brazil contains a complete carbonate sequence that recorded theCretaceousePaleogene transition, and is composed of the Itamaracá, Gramame and Maria Farinhaformations. In this study, the behavior of C and O isotopes, major and trace element chemistry have beenexamined in core drill carbonate samples from three drill holes (Poty Quarry, Olinda and Itamaracá).The deposition of car...
An integrated IDTIMS, EVTIMS and SHRIMP zircon dating study
Ferreira, Valderez P.