Permian bivalve molluscs from the Gai-As Formation, northern Namibia: systematics, taphonomy and biostratigraphy
Nenhuma Miniatura disponível
Data
2011-01-01
Autores
David, Juliana M. [UNESP]
Simoes, Marcello G.
Anelli, Luiz E.
Rohn, Rosemarie
Holzfoerster, Frank
Título da Revista
ISSN da Revista
Título de Volume
Editor
Taylor & Francis Ltd
Resumo
Fossil bivalves from two horizons in the Gai-As Formation of NW Namibia are tentatively correlated with mid-Permian taxa of the Passa Dois Group of Brazil, supporting the concept that the Parana Basin extended into Africa. The Namibian fauna includes a new genus and species, Huabiella compressa, which was previously confused with Brazilian taxa. The taphonomy of the bivalve-rich strata indicates deposition under the influence of episodic events, such as storms. The Gai-As Formation directly overlies the mesosaurid-bearing deposits of the Huab Formation, indicating a significant unconformity when compared with the more complete succession of the Passa Dois Group, Parana Basin, Brazil. The studied bivalve assemblages are no younger than 265+/-2.5Ma (mid-Permian), based on U/Pb radiometric dating of zircons from tuffs.
Descrição
Palavras-chave
Bivalvia, Megadesmidae, Permian, Huab area, Gai-As Formation, biostratigraphy, Rio do Rasto Formation
Como citar
Alcheringa. Abingdon: Taylor & Francis Ltd, v. 35, n. 4, p. 497-516, 2011.