2019-11-072019-11-072013-04-08MEDEIROS, Renato Sol Paiva de. Reconstituição paleoambiental da Formação Pedra de Fogo na borda oeste da Bacia do Parnaíba, na região de Araguaína (To). Orientador: Afonso César Rodrigues Nogueira. 2013. 126 f. Trabalho de Curso (Bacharelado em Geologia) - Faculdade de Geologia, Instituto de Geociências, Universidade Federal do Pará, Belém, 2013. Disponível em: https://bdm.ufpa.br/jspui/handle/prefix/2428. Acesso em:.https://bdm.ufpa.br/jspui/handle/prefix/2428The Pedra de Fogo Formation in Parnaíba Basin, Araguaína region, Tocantins, is spread laterally for tens of kilometers being predominantly represented by pelitic facies. The faciological and stratigraphic analysis allowed the characterization of 11 facies grouped in three facies associations (AF), predominantly representing a lagoonal paleoenvironment associated with a eolian dunes field. The lagoonal deposits are divided into: a) central lagoon (AF1) predominantly composed of siltstone with planar lamination (facies Sl), sandstone interbedded with siltstone showing slightly undulate lamination (facies Al) and massive siltstone (facies Sm), forming several coarsening-upward metre-scale cycles with the bed thicknesses thickening up to the top. In the intermediate cycles from this formation were found undifferentiated bioclasts in a thin section. b) marginal lagoon (AF2) is characterized mainly for facies Al, sandstone with cross-lamination (facies Ac), sandstone with swaley cross-stratification (facies As), massive sandstone with evaporitic structures (facies Av), sandstone with mudcracks (facies Ag) and massive sandstone (Am). In basal cycles of this AF there are found large amounts of fossiliferous material, in highlight the fish of the class Chondrichthyes. This facies association has a higher deposition during the shallowing of the lagoon in drought periods. c) In facies association eolian dunes field (AF3) are described as restricted deposits represented by facies sandstone with tabular cross-stratification (facies Ae) and sandstone with planar stratification (facies App), fine-grained and thin sets.The Permian deposits of the Pedra de Fogo Formation in the Parnaíba Basin are associated with dry climates under continuous rising temperatures leading to Greenhouse events. The deposits described are associated with lacustrine environment, described as a lagoon which led to a playa lake type later covered by eolian dunes, typical of desert environments existing in the region during the Permian-Triassic passage.Acesso AbertoGeologia estratigráfica - PermianoReconstituição paleoambientalFormação Pedra de FogoBacia do ParnaíbaCNPQ::CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS::GEOLOGIA::ESTRATIGRAFIATrabalho de Curso - Graduação - Monografia