Fossil diversity and taphonomy of glacial and post-glacial lower paleozoic strata, NE Paran ` a Basin, Brazil

Autor(es)

Zabini, Carolina ^[1] ; Denezine, Matheus ^[2] ; Rodrigues, Livia C. da S. ^[2] ; Goncalves, Livio R. de O. ^[2] ; Adorno, Rodrigo R. ^[3] ; do Carmo, Dermeval ^[2] ; Assine, Mario L. ^[4]

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Geosci Inst, Campinas, SP - Brazil

^[2] Univ Brasilia, Geosci Inst, Brasilia, DF - Brazil

^[3] Ctr Technol Innovat CEDES Setor Banciirio Norte, BR-70040904 Brasilia, DF - Brazil

^[4] UNESP, Dept Geol, Sao Paulo State Univ, Rio Claro, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of South American Earth Sciences; v. 111, NOV 2021.
• Citações Web of Science: 0

Resumo

Unlike other South American basins, the boundary between Ordovician and Silurian in the Paran ` a Basin, Brazil, has yet to be studied in detail. This article reports the occurrence and taphonomic analysis of a fauna composed of the organophosphatic brachiopods Kosoidea australis and ?Palaeoglossa sp., the mollusks ?Paleoneilo sp. and ? Cuneamya sp., besides rynchonelliform brachiopods and the ostracods Harpabollia sp. and Satiellina paranaensis. This assemblage indicates a Hirnantian age for the top of the Iap ` o and the base of the Vila Maria formations, northeastern border of the Paran ` a Basin. Taphonomic signatures and facies associations point to a pro-glacial environment, at the transitional shoreface, represented by the last sedimentary facies of the Iap ` o Formation. The overlying transgressive strata represent the beginning of the Vila Maria Formation, in which fossils and lithofacies indicate predominant post-glacial conditions in an offshore setting. Two taphofacies were delineated. One features size- and type-selected fossils, deposited in rain-out facies originated from the melting glacier. The second, with autochthonous to parautochthonous fossils, represents a post-glacial offshore setting. The low faunal diversity points to marine connections between North and South African basins, and with South American basins. (AU)

• Processo FAPESP: 17/10956-5 - Taxonomia e análise fossildiagenética dos lingulídeos paleozoicos das Bacias do Paraná e Parnaíba
• Beneficiário: Carolina Zabini
• Modalidade de apoio: Auxílio à Pesquisa - Regular