info:eu-repo/semantics/article
CONTRIBUIÇÃO À GEOLOGIA E PETROLOGIA DA REGIÃO DE SÃO DOMINGOS. GO
CONTRIBUIÇÃO À GEOLOGIA E PETROLOGIA DA REGIÃO DE SÃO DOMINGOS. GO
Autor
TEIXEIRA, NOEVALDO ARAÚJO
POLI, ALFREDO JOSÉ CUPERTINO
FERREIRA, MARIA CELENE BARBOSA
Institución
Resumen
The São Domingos Sequence (NE of Goiás State ), previously considered as belonging to the Araxá Group, is characterized as a small metamorphic belt of the greenschist facies, locally sectioned by plutonic bodies (stocks) of granitic and tonalitic composition. It is underlain by the gneiss-migmatitic sialic basement and is unconformably overlain by carbonate sediments of the Bambui Group. The sequence consists of muscovite-garnet-biotite schists, feldspathic schists, biotite-calcite-muscovite schists, amphybole schists, biotite phyllites, graphite phyllites, and ferrous quartzites. These rocks were probably derived from an assemblage of sedimentary (greywacke, pelite, ironstone) and basic and acid volcanic rocks, the latter chemically characterized as being respectively of continental tholeitic and calcalkaline types.The sequence shows a volcano-sedimentary assemblage, which differs greatly from those of the Araxá Group and its lateral facies (Arai, Natividade, and Canastra Groups). In addition, the occurence of acid plutonism, uncommon within those units, leads to a possible correlation with the Ticunzal Formation. The São Domingos Sequence (NE of Goiás State ), previously considered as belonging to the Araxá Group, is characterized as a small metamorphic belt of the greenschist facies, locally sectioned by plutonic bodies (stocks) of granitic and tonalitic composition. It is underlain by the gneiss-migmatitic sialic basement and is unconformably overlain by carbonate sediments of the Bambui Group. The sequence consists of muscovite-garnet-biotite schists, feldspathic schists, biotite-calcite-muscovite schists, amphybole schists, biotite phyllites, graphite phyllites, and ferrous quartzites. These rocks were probably derived from an assemblage of sedimentary (greywacke, pelite, ironstone) and basic and acid volcanic rocks, the latter chemically characterized as being respectively of continental tholeitic and calcalkaline types.The sequence shows a volcano-sedimentary assemblage, which differs greatly from those of the Araxá Group and its lateral facies (Arai, Natividade, and Canastra Groups). In addition, the occurence of acid plutonism, uncommon within those units, leads to a possible correlation with the Ticunzal Formation.