The Early Cretaceous Jacui Group, a newly discovered volcaniclastic-epiclastic accumulation at the top of the Parana Basin, southern Brazil

Autor(es)

Riccomini, Claudio ^{[1, 2, 3]} ; Sant'Anna, Lucy Gomes ^{[2, 4]} ; Fambrini, Gelson Luis ^[5]

Afiliação do(s) autor(es)

^[1] CNPQ, Sao Paulo - Brazil

^[2] Univ Sao Paulo, Inst Energy & Environm, Ave Prof Luciano Gualberto 1289, BR-05508010 Sao Paulo, SP - Brazil

^[3] Univ Sao Paulo, Inst Geosci, Rua Lago 562, BR-05508080 Sao Paulo, SP - Brazil

^[4] Univ Sao Paulo, Sch Arts Sci & Humanities, Ave Arlindo Bettio 1000, BR-03828000 Sao Paulo, SP - Brazil

^[5] Univ Fed Pernambuco, Ctr Technol & Geosci, Ave Acad Helio Ramos S-N, BR-50740530 Recife, PE - Brazil

• Tipo de documento: Artigo Científico
• Fonte: CRETACEOUS RESEARCH; v. 59, p. 111-128, APR 2016.
• Citações Web of Science: 9

Resumo

The presence of volcaniclastic rocks related to the silicic magmatism within the Serra Geral Formation has been a matter of long-standing debate. In this paper, we present extensive documentation that supports the presence and abundance of these rocks in the Jacui Group, a newly discovered volcaniclastic and epiclastic accumulation in southern Brazil. The Jacui Group is composed of two interfingered stratigraphic units, the Volta Alegre and Tupancireta formations, and it represents the uppermost stratigraphic unit of the Parana Basin. The Volta Alegre Formation is primarily composed of resedimented volcaniclastic tuffites, the pyroclasts which were sourced from the Santa Maria subgroup of the Palmas type of the Serra Geral Formation. The Tupancireta Formation is composed of fluvial and aeolian deposits transported towards the north northwest. Deposition of the Jacul Group began in the Early Cretaceous (similar to 132 Ma) and was coeval with the acidic volcanism of the Santa Maria subgroup. This group was deposited in a probable interior sag basin that represents either the beginning of the extension in the inner part of the continent that subsequently migrated to the east or the far-field impact of extensional processes that preceded the break-up of Gondwana and the opening of the South Atlantic Ocean. (C) 2015 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 07/58319-1 - Proveniencia de sedimentos neogenos da area de confluencia dos rios negro e solimoes, amazonia.
• Beneficiário: Lucy Gomes Sant'Anna
• Modalidade de apoio: Auxílio à Pesquisa - Regular