Contribuição à geologia da região de frades, município de Teresópolis (Rio de Janeiro)

A geological mapping at the scale 1:50,000 based on air photographs at the scale 1:20.000 is being held near Frades, a small village between Teresopolis and Nova Friburgo, State of Rio de Janeiro, Brazil. The main rock types are a coarse grained gneiss, migmatites and granites. The pigmatites exibits a dark differentiate (melanosome), sometimes widespread in area, which has been mapped as amphibolite sensu strictu. The latter, until now considered of magmatic origin, seems to have formed through migmatization processes.