The Neoproterozoic (580 ± 20 Ma) alkaline granitoid magmatism produced two rock associations in the Serra do Mar region, Southern Brazil. The first one (70-76% SiO 2 ) is metaluminous to weakly peraluminous, HFSE depleted relative to LILE, and includes the larger massifs mainly. The second one (62-76% SiO 2 ) comprises metaluminous as well as peralkaline rock-types and is enriched in HFSE relative to LILE. The granitoid massifs were emplaced within transtensional fault zones generated during

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... final stages of the agglutination process that led to the formation of the Gondwana supercontinent. As a whole, the Serra do Mar granitoid magmatism represents a transition from late orogenic calc-alkaline monzonitic to anorogenic alkaline (A-type) magmatism.