| Texto completo | |
| Autor(es): |
Jurigan, Isabela
[1]
;
Ricardi-Branco, Fresia
[1]
;
Neregato, Rodrigo
[2]
;
Saraiva dos Santos, Ticiano Jose
[1]
Número total de Autores: 4
|
| Afiliação do(s) autor(es): | [1] Univ Estadual Campinas, Geosci Inst, Carlos Gomes 250, BR-13083855 Campinas, SP - Brazil
[2] Univ Rio Grande do Sul, POB 15001, BR-91501970 Porto Alegre, RS - Brazil
Número total de Afiliações: 2
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Journal of South American Earth Sciences; v. 96, DEC 2019. |
| Citações Web of Science: | 0 |
| Resumo | |
Tonsteins are layers generated from volcanic ash fall and constitute an important chronostratigraphic marker that allows the correlation between layers in and out of the sedimentary basin, as well as the calibration of biostratigraphic frameworks. In this contribution a new occurrence of tonstein is reported associated with the coal seams in Parana state, in the Parana Basin, and it was used as a tie point in local and intra-Gondwanan palynostratigraphy. First, the volcanic origin of the layer was attested by using methods as petrography, SEM and XRD. Then, the layer was dated by U-Pb zircon with LA-ICP-MS method, obtaining an age of 286 +/- 3 Ma which corresponds to the Artinskian (middle Cisuralian), thus the layers are correlated with the coal seam from Faxinal coalfield. However, the palynostratigraphic position for the studied interval was at the Protohaploxypinus goraiensis Subzone (lower Vittatina costabilis Zone), due to the presence of Protohaploxypinus goraiensis, Illinites unicus, Vittatina, and Converrucosisporites confiuens while palynostratigraphy of Faxinal places it at the Hamiapollenites karooensis Subzone (upper Vittatina costabdis Zone). Therefore, one possible explanation is that the boundary between the subzones of Vittatina costabilis Zone is younger on the studied site than in the rest of the basin. (AU) | |
| Processo FAPESP: | 16/20927-0 - Estudos de acumulações modernas e fósseis de bioclastos em ambientes continentais e costeiros. |
| Beneficiário: | Fresia Soledad Ricardi Torres Branco |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |