Geochemistry and petrogenesis of the Mesoarchean granites from the Canaa dos Carajas area, Carajas Province, Brazil: Implications for the origin of Archean granites

摘要

Four Mesoarchean (2.93 to 2.83 Ga) granite units, which encompass the Canaa dos Carajas, Bom Jesus, Cruzadao and Serra Dourada granites, were recognized in the Canaa dos Carajas area of the Archean Carajas Province. The Mesoarchean units are composed dominandy of biotite leucomonzogranites. They are compared with the Neoarchean Planalto suite (2.73Ga) which encompasses biotite-hornblende monzogranites to syenogranites. The Canaa dos Carajas, Bom Jesus and the variety of the Cruzadao granite with higher (La/Yb)N are geochemically more al