Abstract
This paper discusses the geology of the manganese deposits of Bandarra within the Licinio de Almeida Complex, southern Bahia. Hogback and "cuesta" morfologies are typical of the region. The lithologic units consist, from base to top, of three sequences: a) micaschists; b) banded iron-formation; and c) micaschists, amphibolites and quartzites. The manganese ore bodies can be classified as primary (lenticular) and secondary (eluvial and colluvial). The primary ores are ferruginous (25-30% of Fe and 10% of Mn), manganiferous (45-55% of Mn), siliceous (30-40% of Si0(2) and 10-20% of Mn) and occurs associated to iron-formations. The secondary ores are constituted by rolled material of the granzon type. The protore, named "bandarrito", constituties of oxide-carbonate facies manganiferous iron-formation. The micaschists contain andesine and the amphibolites hornblende-plagioclase-epidote, typifying the almandine-amphibolite metamorphic facies. The local structure trend mainly NE-SW with a northwest vergenz. Different styles of folding indicate at least two deformation episodes.
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