Data/hora: 10/06/2024 09:20:20

Provedor de dados: | Anais da Academia Brasileira de Ciências
País: | Brazil
Título: | Araçatuba Formation: palustrine deposits from the initial sedimentation phase of the Bauru Basin
Autores: | Fernandes,Luiz A.; Giannini,Paulo C. F.; Góes,Ana Maria.
Data: | 2003-06-01
Ano: | 2003
Palavras-chave: | Araçatuba; Cretaceous; Bauru; Swamp; Palustrine; Continental.
Resumo: | The Bauru Basin (Upper Cretaceous) accumulated an essentially sandy continental sedimentary sequence. In a first desertic phase the basaltic substratum was covered by a widespread and homogeneous aeolian sand unit with minor loess intercalations. The substratum relief favored the formation of an endorheic drainage system under semi-arid climate, a process that started the development of the Araçatuba Paleoswamp. The palustrine deposits (Araçatuba Formation) comprise siltstone and tipically greenish gray narrow tabular strata of sandstone cemented by carbonate. Moulds and gypsite and dolomite pseudomorphs were identified. The moulds seem to be genetically associated with desiccation cracks, root marks and climbing ripple lamination levels, that, on the whole, indicate calm shallow saline waters undergoing phases of subaerial exposition. At the boundaries of the study area, sand units may exhibit sigmoidal features and convolute bedding structure, which is characteristic of marginal deltaic deposits. The Araçatuba Formation is enclosed in and later overlaid by the aeolian deposits of the Vale do Rio do Peixe Formation.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652003000200006
Editor: | Academia Brasileira de Ciências
Relação: | 10.1590/S0001-37652003000200006
Formato: | text/html
Fonte: | Anais da Academia Brasileira de Ciências  v.75 n.2 2003
Fonte: | info:eu-repo/semantics/openAccess