| Texto completo | |
| Autor(es): |
Franco, Lucca Martins
;
Tupinamba, Miguel
;
La Terra, Emanuele Francesco
;
Panetto, Liliane Paiva
;
Azzone, Rogerio Guitarrari
Número total de Autores: 5
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Journal of South American Earth Sciences; v. 172, p. 20-pg., 2026-03-01. |
| Resumo | |
Here, we provide some structural and mineralogical evidence about what happens below a volcanic field during precursor seismic events. Based on outcrops and borehole material, we analyzed volcanic-related structures within the Cretaceous volcanic sequence of the Alto Parana & iacute;ba Igneous Province and the underlying Areado Group sandstones in southeastern Brazil, focusing on the role of magmatic volatiles and magmatic fluid circulation. Structural, petrographic, and geochemical data indicate that magma ascent through subvertical conduits generated overpressure conditions, promoting carbonate-rich hydrothermal activity and widespread deformation. The resulting structural assemblage includes normal faults, deformation bands, localized folding, subhorizontal creeping faults, and soft-sediment deformation structures, particularly concentrated at sandstone-volcanic contacts. Geological profiles highlight the mechanical and hydraulic interaction between alkaline rocks and their sedimentary host. Overall, the results indicate that volatile exsolution during magma ascent was a key driver of fluid-assisted brittle deformation and induced seismicity, exerting first-order control on fault development, sediment destabilization, and hydrothermal alteration. (AU) | |
| Processo FAPESP: | 23/11675-0 - Corpos magmáticos de afinidade básica-ultrabásica insaturados em SiO2 da plataforma brasileira: estudo de fontes e processos de evolução em sistema aberto em complex plumbing systems a partir de abordagem microanalítica |
| Beneficiário: | Rogério Guitarrari Azzone |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |