Alteração e concentração ferruginosa no arenito do Membro Serra da Galga (Triângulo Mineiro - MG)

• Autor(a) principal: Mariano, Érika [UNESP]
• Data de Publicação: 2016
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/149724; http://www.athena.biblioteca.unesp.br/exlibris/bd/capelo/2016-12-05/000873426.pdf
• topic: Petrologia; Arenito; Sedimentação e depósitos; Sedimentos (Geologia); Solos - Composição; Laterita; Minerais; Triangulo Mineiro (MG)

The origin of ferruginous sediments in the Triângulo Mineiro sedimentary plateau has never been previously studied. This work relates the sandstone of Serra da Galga Member with those ferruginous levels, intending to evaluate the possible formation of a ferruginous layer by lateritic processes. In Brazil, 75% of the surface is covered by lateritic layer, formed from the alteration of rocks in tectonically stable environment with seasonal tropical climate. The Triângulo Mineiro has the characteristics that favor lateritization, therefore, the work is developed from the petrographic analysis of a weathering profile of Serra da Galga Member, examining the change of the sandstones primary minerals and its evolution through the weathering. The observations and micromorphological descriptions of parental material and its weathering products provide important information about the newly formed secondary minerals and, when combined with geochemical and mineralogical data, allow us to interpret the relationship of the original material (sandstone) with ferruginous layer. The analysis compares the primary and secondary minerals, structures and textures over weathering profile