BDTD - Biblioteca Digital de Teses e Dissertações
URI Permanente desta comunidadehttps://repositorio.ufpa.br/handle/2011/2289
Biblioteca Digital de Teses e Dissertações da UFPA (BDTD). Sistema Eletrônico de Teses e Dissertações (TEDE). Projeto BDTD/UFPA e Instituto Brasileiro de Informação em Ciência e Tecnologia (IBICT).
Navegar
Navegando BDTD - Biblioteca Digital de Teses e Dissertações por Orientadores "AGUILERA SOCORRO, Orangel Antonio"
Agora exibindo 1 - 3 de 3
- Resultados por página
- Opções de Ordenação
Item Acesso aberto (Open Access) Estudo paleontológico do limite oligoceno/mioceno nas formações Ilha de Santana e Pirabas nas bacias Pará-Maranhão e Barreirinhas na plataforma equatorial noroeste do Brasil.(Universidade Federal do Pará, 2023-12-14) GUIMARÃES, Beatriz Teixeira; AGUILERA SOCORRO, Orangel Antonio; http://lattes.cnpq.br/5854051483674293; https://orcid.org/0000-0003-4418-8351Sedimentary carbonate outcrops of the Pirabas Formation at the Bragantina Platform in North Brazil represent the exposed portion of the entire carbonate succession in the marine equatorial platform from the subsurface Ilha de Santana Formation (Cretaceous/Maastrichtian-Miocene/Aquitanian) in the Pará-Maranhão Basin and from the Formation Pirabas (Miocene/Aquitanian-Serravallian) in the Barreirinhas Basin, both from the Humberto de Campos Group. The transgressive deposit, flooding, and advance of the carbonate platform were investigated through the study of outcrops of the Pirabas Formation (type locality in the Ilha de Fortaleza, Pará state) and the analogous carbonate of the upper section of the Ilha de Santana Formation of the well-log 1- MAS-16-MA (510 to 660 meters below the seabed). The stratigraphic analyses were based on petrography, microCT, microfossil assemblages (foraminifers, ostracods, and bryozoans) and index species (Amphistegina, Archaias, Pyrgo, Quinqueloculina, Pirabasoporella, Nellia, Skylonia, and Alpheus), and biofacies approach. The boundary between the Ilha de Santana Formation (Aquitanian/Burdigalian at 510–660 m section of 1-MAS-16-MA) and the Pirabas Formation (Burdigalian/Serravallian at the Ilha de Fortaleza outcrop) suggests that shallow-water sedimentary facies are similar to those deposited in the marginal basins and marks the start of siliciclastic supplies to the inner platform and the reduction of coralline algal carbonate factories.Item Acesso aberto (Open Access) Flora e fauna do neógeno das áreas de manguezais de lagoas costeiras da plataforma equatorial do Brasil: processo de piritização(Universidade Federal do Pará, 2021-04-02) MATA, Giovanni Alvaro Teixeira da; AGUILERA SOCORRO, Orangel Antonio; http://lattes.cnpq.br/5854051483674293; https://orcid.org/0000-0003-4418-8351The carbonate-siliciclastic rocks from the early to middle Miocene Pirabas Formation in the equatorial margin of Brazil show a brackish ecofacies of mangrove and coastal lagoons paleoenvironments under tidal influence. The studied section has dark mudstone at the top, characterized by a microbial methanogenesis zone where pyritized trunks, leaves, micro- and macrofossils, and trace fossils, have been investigated. The petrographic characterization and crystallographic analyses distinguish mostly framboids crystal for trunk fragments to the octahedric and cubic crystals from invertebrate shells. The geochemistry analyzes revealed that Fe and S are concentrated both in the fossiliferous content of invertebrate constituents and in the matrix that hosts the trunk, while the other elements are mainly linked to invertebrates. The preferential distribution of these elements is in accordance with the presence of FeS2 compounds replacing fossils, reflecting the anoxic and reducing conditions of the environment. The pyrite-rich lithostratigraphic section was deposited in a shallow water environment, where pyrite mineralization was developed during the early diagenetic stage under anoxic conditions, plenty of organic matter, warm and mixohaline water. The integration of faciological, stratigraphic and chemical data from the carbonate deposits of the Pirabas Formation, in addition to reconstructing the stratigraphic behavior of these units in the period studied, would also assist in understanding the paleoenvironmental and paleogeographic changes of the Bragantina Platform and its possible relationship with global events.Item Acesso aberto (Open Access) Traços fósseis de crustáceos da Formação Pirabas, mioceno da Plataforma Bragantina, NE do Pará.(Universidade Federal do Pará, 2019-09-16) GONÇALVES, Meireanny de Albuquerque; SOARES, Joelson Lima; http://lattes.cnpq.br/1345968080357131; AGUILERA SOCORRO, Orangel Antonio; http://lattes.cnpq.br/5854051483674293The Miocene deposits of the Pirabas Formation present in their fossil records decapods crustaceans of epifauna and infauna. These organisms marked by the presence of ichnofossils that allow the discrimination of the main activities carried out during the construction of these bioturbation. Descriptions of the microfacies in association with the main occurrences of fossil traits in the Pirabas Formation allowed greater interpretations on the distribution and behavior of decapod crustaceans, as well as the main salinity, bathymetry and oxygenation conditions of the paleoenvironment. The described microfacies are mudstone, massive wackestone with echinoderms, packstone rich in foraminifera and mollusks, grainstone with terrigenous and algae, bafflestone with bryozoan and terrigenous, packstone / wackestone with flat lamination, packstone / grainstone with foraminifera and rudstone with fragments of mollusks. The main ichnogenus described are Thalassinoides, Gyrolithes and Sinusichnus individualized in six icnoespecies Thalassinoides suevicus, Thalassinoides paradoxicus, Thalassinoides isp, Gyrolithes dravexi, Gyrolithes krameri, and Sinusichnus sinuosos. This trace assembly presents characteristics typical of the Cruziana icnofacies composed mainly of predominantly horizontal buildings of housing (domichnia) and food (fodinichnia) produced under energy conditions ranging from low to moderate levels. The quantification of bioturbation allowed the distinction of three icnofábrica denominated icrofábrica Gyrolithes, icnofábrica Sinusichnus and icnofábrica dominated by Thalassinoides whose rates of bioturbation vary between ii = 2, with rates of 10-15% up to ii = 4 whose rates are of 35-65%.These indices indicate the progressive increase of bioturbation intensity from the association of tidal flat, laguna to the association of bioclastic barrier. Petrographic analysis, SEM (Scanning Electron Microscope), EDS (Dispersive Energy Spectroscopy) and DR-X (Xray Diffraction) indicated different compositions in the filling of the trace compatible with reduced microenvironments also proven by the presence of pyrite concretions. and siderite, interpreted as a reflection of the interaction of microorganisms with organic matter and the reduction of available sulfate in and around excavations.