Conchostráceos como evidência de níveis jurássicos na Formação Caturrita, Faxinal do Soturno, Rio Grande do Sul, Brasil

Nenhuma Miniatura disponível

Data

2014-01-01

Orientador

Coorientador

Pós-graduação

Curso de graduação

Título da Revista

ISSN da Revista

Título de Volume

Editor

Tipo

Artigo

Direito de acesso

Acesso restrito

Resumo

This paper focus on the first conchostracans (Crustacea, Spinicaudata) found at the São Luís outcrop (Caturrita Formation, Rosário do Sul Group), in Faxinal do Soturno, Rio Grande do Sul State, Brazil (29° 33' 29.09S, 53° 26' 54W). Fossil vertebrates and plants identified at this outcrop suggest conflicting ages, respectively Late Triassic and Early Jurassic. Dinosaur tracks recently found at the upper part of the outcrop enhance these age problems. In this way, the conchostracans constitute important additional elements in this discussion. Some specimens share many characteristics with Carapacestheria disgregaris (Tasch) Shen (Eosestheriidae) of the Ferrar Group, Lower-Mid Jurassic of the Transantartic Mountains. But differences in the ornamentation details led to the proposal of a new genus and a new species, Nothocarapacestheria soturnensis, and to the interpretation of a close phylogenetic relationship with the Antarctic species. Other samples in this assemblage are similar to Australestheria corneti (Marliére) Chen (Fushunograptidae) of the Middle Jurassic from Zaire. Together, these conchostracans substantiate a Jurassic age and corroborate the data of the Bennettitales flora found at the same levels in the outcrop. However, the Late Triassic age indicated by the tetrapods cannot be discarded according to their lower stratigraphic position in São Luís outcrop. In the same way, the present chronostratigraphic discussion does not apply to the other occurrences of the Caturrita Formation, especially because the correlations between outcrops are extremely difficult, both by the lack of paleontological support and by the numerous faultings during the Mesozoic sedimentation in the southern part of the Paraná Basin.

Descrição

Idioma

Português

Como citar

Geologia USP - Serie Cientifica, v. 14, n. 1, p. 3-20, 2014.

Itens relacionados

Financiadores

Coleções