info:eu-repo/semantics/article
GEOCHEMISTRY AND PETROLOGY OF FELSIC AND MAFIC SUITES RELATED TO THE PALEOPROTEROZOIC TRANSAMAZONIAN OROGENY IN MINAS GERAIS, BRAZIL
GEOCHEMISTRY AND PETROLOGY OF FELSIC AND MAFIC SUITES RELATED TO THE PALEOPROTEROZOIC TRANSAMAZONIAN OROGENY IN MINAS GERAIS, BRAZIL
Autor
QUÉMÉNEUR, JOEL JEAN GABRIEL
NOCE, CARLOS MAURICIO
Institución
Resumen
Paleoproterozoic (ca. 2.0-2.1 Ga) intrusive rocks exposed along the southern border of the São Francisco Craton have been divided into three suites: granite suite, TTG (tonalite-trondhjemite-granodiorite) suite, and gabro-diorite suite. The granite suite comprises two distinct groups of plutons, one composed of highly differentiated peraluminous granites, and the other including less evolved metaluminous to peraluminous high-K granites. It is suggested that granitic plutons are not derived from a single magma source, probably due to their association to more than one stage of the orogen evolution. TTG and gabro-diorite suites follow a calc-alkaline trend, and may constitute a single large suite originated from mantle-derived magmas at a plate margin setting. However, chemical data of some granodioritic plutons of the TTG suite indicates contribution of crust-derived material. Paleoproterozoic (ca. 2.0-2.1 Ga) intrusive rocks exposed along the southern border of the São Francisco Craton have been divided into three suites: granite suite, TTG (tonalite-trondhjemite-granodiorite) suite, and gabro-diorite suite. The granite suite comprises two distinct groups of plutons, one composed of highly differentiated peraluminous granites, and the other including less evolved metaluminous to peraluminous high-K granites. It is suggested that granitic plutons are not derived from a single magma source, probably due to their association to more than one stage of the orogen evolution. TTG and gabro-diorite suites follow a calc-alkaline trend, and may constitute a single large suite originated from mantle-derived magmas at a plate margin setting. However, chemical data of some granodioritic plutons of the TTG suite indicates contribution of crust-derived material.