| Texto completo | |
| Autor(es): |
Mohr, Ingrid Muller
;
de Lima, Evandro Fernandes
;
Rossetti, Lucas de Magalhaes May
;
Rossetti, May
;
de Lima, Tiago Saldanha
;
Meucci, Marcelo Canals
;
Brose, Gabriel Calzia
Número total de Autores: 7
|
| Tipo de documento: | Artigo Científico |
| Fonte: | JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH; v. 470, p. 20-pg., 2026-02-01. |
| Resumo | |
The initial phase of volcanism in continental flood basalt provinces (CFBPs) is typically characterised by a wide range of lava morphologies and emplacement dynamics. Early-stage volcanism commonly involves low-volume pa<overline>hoehoe flows emplaced over geologically short periods. These volcanic successions may include interactions with pre-existing sediments and occasional volcaniclastic accumulations, although in some settings, CFBPs are emplaced directly on the basement. The Torres Formation marks the onset of volcanism in the southern Parana Igneous Province. In the Brazilian sector, this volcanism is referred to as the Serra Geral Group (135-132 Ma), which mainly consists of volcanic and intrusive rocks of tholeiitic affinity overlying the aeolian sandstones of the Botucatu Formation. The Torres Formation is characterised by a volcano-sedimentary sequence dominated by lobes, sheet, and ponded pa<overline>hoehoe lava flows, with an average cumulative thickness of approximately 200 m. These early flows covered and interacted with aeolian sandstones at the base of the volcanic pile. Siliciclastic intertraps mark quiescent periods in volcanic activity and are interbedded with the lava flows. Petrographically, the flows exhibit similar mineral assemblages, with rare presence of olivine, but have differences in plagioclase and pyroxene proportions. Texturally, the flows vary in crystallinity, grain size, and phenocryst abundance. The flows with sheet and lobes morphologies are geochemically more primitive than the ponded lavas. These features, recorded in the Torres Formation, reflect the complex interplay between magma supply, emplacement environment, and surface processes during the initial eruptive phase of this CFBP. (AU) | |
| Processo FAPESP: | 23/00150-4 - Análise das redes de apoio social em situações de perda fetal |
| Beneficiário: | Julie Higuti Fukushima |
| Modalidade de apoio: | Bolsas no Brasil - Iniciação Científica |
| Processo FAPESP: | 19/22084-8 - A Província Magmática Paraná: petrogênese, cronologia e impacto ambiental do magmatismo toleítico, alcalino e silícico Cretáceo na Plataforma Brasileira |
| Beneficiário: | Valdecir de Assis Janasi |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |