GEOCHEMISTRY AND PETROLOGY OF FELSIC AND MAFIC SUITES RELATED TO THE PALEOPROTEROZOIC TRANSAMAZONIAN OROGENY IN MINAS GERAIS, BRAZIL

JOEL JEAN GABRIEL QUÉMÉNEUR, CARLOS MAURICIO NOCE

Resumo


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.

Palavras-chave


Geochemistry; Petrology; Felsic suites; Mafic suites; Paleoproterozoic.

Texto completo:

PDF (English)

Apontamentos

  • Não há apontamentos.