Abstract
The observed mineral assemblages in metapelites of Araxá Group, in Goiás, are related to metamorphic peak, are typical of medium to upper amphibolite facies conditions and correlated to either an early stage of the main ductile deformation phase (Dn) observed in the region, or even to a previous deformation phase. The metamorphic peak is marked by the following mineral assemblage: quartz, biotite, garnet, plagioclase, kyanite ± staurolite; sillimanite is produced later during decompression. Intense retrometamorphism is observed in several samples, in which garnet is replaced by chlorite and later random grains of muscovite overgrew main foliation. Thermobarometry points to 610 ºC and 9.5 kbar as metamorphic peak conditions. The P-T path, inferred with textural and thermobarometric data, is clockwise, compatible with a collisional setting and similar with other P-T paths observed in other parts of Brasília Fold Belt.
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